Fluff vs. Mechanics

[eftexar]

Well, are you going to answer your own question? I, mean, it does have an answer.

I would assume he would risk losing his licence. He would at least have to face a review board. He might even face trial and go to jail. Does he stop being a Doctor? That's a harder question to answer. Philosophically, perhaps yes. Educationally, perhaps no. Even if you don't consider him a Doctor anymore, he still has all his skills as a Doctor. It might just be illegal to use them. Applying Mechanics to the real world, he doesn't suddenly forget to use a scalpel because he broke his oath or "he can no longer be considered a Doctor."

Not sure what you are trying to prove here. I answered your question, no one answered mine.

What happens to a Druid who wears Metal Armor?

There must be an answer to this too. What is it? What does the Player's Handbook indicate?

I suppose you could say, "the Druid loses all Magical abilities related to Nature" at the harshest. As a DM you even have that right (whether it is fair or not). But the Druid CAN wear the Metal Armor despite the penalties. And, this would still be a House Rule (not RAW). There is no written indication of "what happens when a Druid wears Metal Armor" that I can see.

---

I can break your question down more if that's what you want?

The Law (likely) indicates : If a Doctor endangers other people, he has broken the law. He broke the law, so he may face consequences. Losing his license, trial, jail, etc . . .

With the question about the Druid and Metal Armor :

The Rule should indicate : If the Druid wears Metal Armor, this . . . has happened. And these . . . are the consequences.

Clearly, the Doctor CAN break the Law. Reality itself doesn't interfere with free will.

Clearly, the Druid CAN wear Metal Armor. No Rule indicates the Druid can't.

You can say "the Druid WON'T" all you want. This makes it no more True than "the Doctor WON'T break his Hippocratic Oath." This merely indicates "how things should be" and not "what they are in actuality." It also doesn't account for all the "except when(s)" that exist.

---

The problem with "The Druid won't wear Metal Armor," as an absolute paradigm and Rule (rather than just Fluff), is that it takes away free will. From both the Player and the Character. There is no context in which I WON'T literaly means I CAN'T.

[Daphne]

What happens to a Druid who wears Metal Armor?

Like most things in this edition: ask your DM.

[Kane0]

Like most things in this edition: ask your DM.

What Ef is getting at is that you can’t ask the PHB or DMG, you HAVE to ask your DM

Edit: which in 5e’s terms makes it a ruling, not a rule.

[Deadfire182]

Like most things in this edition: ask your DM.

I don't have to ask my DM why I shouldn't wear armor as a monk. It's written right there in the handbook that I lose my martial arts abilities. Why is Druid different?

Because it's a poorly worded rule that could be changed to stop grand interpretations like those present here.

Regardless, I do believe that if you're going full RAW, then nothing happens to the Druid who puts on/is forced into metal armor. Nothing out of the ordinary at all. Now, nobody fully goes by RAW, nor should they, so really there could be consequences if that's what your DM wants, but yeah, RAW nothing happens.

[eftexar]

Daphne, you are late to the discussion so I'll fill you in (so you don't have to read the "tldr" text) . . .

It's not about what the DM decides or what the final conclusion is. The only question here, is "What happens to the Druid if he wears Metal Armor?"

I am not debating the DM's right to adjucate or adjust the Rules as needed. I am debating whether or not, as per RAW (without DM interpertation), how the Rule, if it is one and not just Fluff, could work.

To rephrase : In all honesty I don't care what the DMs decision is. I would probably go along with it (even if he said, "You aren't Proficient with that Armor" or "You lose your Spellcasting while wearing that Armor"). That isn't the point I'm making. I'm not arguing for or against the DM making a decision. I'm trying to press the point that the PH can't give you this answer. If you have to have a DM answer it, it is a House Rule.

---

Edit :

I think I've beaten my point to death now. Not much more I can say, ways I can phrase it, or ways I can explain it. So, we can actually talk about what we think would be fair if people want to. Personally, if I was the DM, I would take in a number of factors, before ruling :

Spoiler: Factors

Show

As a DM, how would this affect my Story?
As a DM, how would this affect game play and balance?
As a DM, what do I think is fair?
As a Player, can I justify my Character's proposed difference from the norm?
As a Player, how can I justify it?
As a Player, what do I think is fair?
As a DM, what, if I was a Player, do I think is fair?

[Kane0]

It's not about what the DM decides or what the final conclusion is. The only question here, is "What happens to the Druid if he wears Metal Armor?"

The Druid is now wearing armor, and I presume other Druids say mean things about them.

That isn't the point I'm making. I'm not arguing for or against the DM making a decision. I'm trying to press the point that the PH can't give you this answer. If you have to have a DM answer it, it is a House Rule.

You might mean ruling rather than houserule. They’re slightly different

[eftexar]

Lol, Kane0, funny and. . . Perfectly acceptable. I would expect a stricter ruling, but ok. As long as it doesn't dictate what I will and won't do, and only what I can and can't do (or imposes some consequences for doing so), it works for me.

Edit :
Ah, yes, perhaps Ruling would be the better word. Some of my 3.5e lingo still slips into my 5e gamer's cant, from time to time. Rulings in 3.5e tended to refer to Errata or Sage Advice.

Edit :
That said, "all the other Druids call him names" is a "ruling" or "Fluff that causes Mechanics," not a Rule.

[Daphne]

What happens if a Cleric doesn't follow his deity?
What happens if the Paladin breaks his oath? (PHB gives some ideas but not rules)
Can a Warlock's Patron take the power back?

Not wearing metal armor is part of the class fantasy, just like the examples above. I do think they could have added the word "willingly" to avoid some corner cases.

I don't see any issue with how this works in this edition, wearing metal armor is taboo and that's it. It's an aspect of roleplaying Druid, nothing bad will necessarily happen if they wear the armor, but it's something all Druids will avoid to do.

[ad_hoc]

The problem with "The Druid won't wear Metal Armor," as an absolute paradigm and Rule (rather than just Fluff), is that it takes away free will. From both the Player and the Character. There is no context in which I WON'T literaly means I CAN'T.

When people play a game they are agreeing to a set of rules.

Those rules put a constraint on their behaviour. They still have free will, it's just that exercising it in contradiction to the agreed upon rules results in them not playing the game anymore.

The answer to the question - "What happens if a druid wears metal armour" is that the player is ejected from the game for not following the rules.

[eftexar]

Daphne, I'm not saying you are wrong in how these things SHOULD be handled. But as presented in the PHB, "the Druid Won't wear Metal Armor," as presented, is terrible and arguably confusing, if we assume it is a literal Rule, and not a Ruling. Forcing everyone to agree with you, "just because," without have a reason, implied or otherwise is never a good idea. And there is a total lack of logic there. Not even game or setting logic can explain that statement. e.g. Vanacian Magic doesn't need to make literal sense; it just needs to make sense in the Context of the game. And it does.

The Cleric and the Paladin are okay though. I CAN do those things. They are Fluff as Mechanics. I know "not following my Deity" or "breaking an Oath" could result in consequences. These are purely cause of Fluff / Roleplaying affecting Mechancis and that is fine. Great. This is Constructive.

And, can a Patron take back their Warlock's power. That depends on the Fluff. Unlike a Cleric, I would assume it's a Contract of sorts. The Context often shows Fiends as trying to corrupt their Contractee(s). So generally, the Contract is : I give you power, and, when you die, I get your Soul. Or, I give you power, and now you owe me such and such as repayment." And, is power given in parcel and I grow it, is it given in parts, or am I channeling the Fiend's power and not my own?

These are all Rulings or Mechanical Consequences derived from Fluff. They are still not Rules, just because I abide by them. In the cases you presented they add to the Narrative and the Simulation. The way the Druid is handled, if we assume "Won't wear Metal Armor" is absolute, enforces Fluff in a way that is Deconstructive and violates the free will of the Character (and Player). It also goes against Precident when compared to other Classes.

Many people regularily violate some of the tenants of their faith. I doubt you would say they aren't - this Religion - because of that. At least, not to their face. Why can you say that with the Druid? They don't for the Monk or the Paladin. And they don't in real life.

As written, it is neither a Rule or Ruling, but a Dictation of How I Think and Behave.


Ad_hoc, * sigh, * . . .
You are still missing the point something terribly. I have not argued against anything in the statement :

When people play a game they are agreeing to a set of rules.

Those rules put a constraint on their behaviour. They still have free will, it's just that exercising it in contradiction to the agreed upon rules results in them not playing the game anymore.

The key phrasing here, "to the agreed upon Rules." If "Druids won't wear Metal Armor" isn't a Rule, how is it agreed upon behaviour?

and this :

The answer to the question - "What happens if a druid wears metal armour" is that the player is ejected from the game for not following the rules.

Rather harsh, but okay. Rather, it is okay only if the Player agreed upon the rules. As you say yourself.

[ad_hoc]

The key phrasing here, "to the agreed upon Rules." If "Druids won't wear Metal Armor" isn't a Rule, how is it agreed upon behaviour?

If you have houseruled it then there is no conflict.

You can do whatever you want with houserules.

Why are you asking other people about the effects of your own houserules?

[eftexar]

Where did I ask other people about my own House Rules or Rules?

I've been talking about, "What is the Rule" "according to the PHB?" "What happens if I wear Metal Armor, despite the fact I'm a Druid?" "How does the PHB indicate we should handle the problem?"

That has nothing to do with House Rules (beyond, perhaps, requiring them to resolve the issue).

Saying "You Can't" is a Rule. Saying "You Won't" is not a Rule. The only time a DM can say "You Won't," by RAW, is when my Character is Mind-Controlled by a Spell or something. Here, Simulative Mechanics overule the Narrative. Which is fine.

[Kane0]

Saying "You Can't" is a Rule. Saying "You Won't" is not a Rule.

“Wont” would have worked fine with some context and consequence provided, but sadly we have neither without a ruling.

[eftexar]

I know. Kane0, it might have still irked me (depending on the wording), but I could have given "Won't" a pass then. I can't expect an unreasonable amount of "perfection." It would have at least been acceptable though with some explanation.

And it makes me angrier, than it should, that people aren't understanding why "Won't" is a problem.

By using "Won't" as an excuse to refuse to answer "Why" or "How," they are abdicating all responsibility of "if they are wrong." It allows one to simply stop thinking ahead and denigrates even the lightest of critical thinking.

If a teenager tells their Mom, "I won't drink booze and drive," it means something different than if a teenager says "I can't drink booze and drive." The first, maybe they mean it and maybe they don't. The second, I assume, I don't know, they broke their legs or something. Kind of impossible to drive that way isn't it?

[ad_hoc]

Saying "You Won't" is not a Rule. The only time a DM can say "You Won't," by RAW, is when my Character is Mind-Controlled by a Spell or something. Here, Simulative Mechanics overule the Narrative. Which is fine.

There is actually a rule which doesn't involve mind controlling magic.

It is "Druids won't wear metal armour."

It's not the DM saying it either. It's the rules of the game. The DM doesn't need to adjudicate it. It is crystal clear.

[eftexar]

---

No, it really isn't "crystal clear."

Me saying "I won't" do -something- is a "Statement of intent." as in; I won't drive a Vehicle, because I don't want to.

Me saying "I can't" do -something- is a(n) immutable "Rule." as in; If my legs are broken, I can't drive a Vehicle.

Someone telling me that "I can't" do -something- is a mutable "Rule." as in; If I don't have a driver's license, the Law says I will be punished if I do drive.

Someone telling me that "I won't" do -something-, means they think I won't -do something-. This isn't a Rule. It, really, doesn't state anything other than what you believe to be true. It's an opinion.

---

I can't recall, off the top of my head, all of the rules regarding English, but there is actually Syntax and Grammar supporting this. You can't just make up your own Grammer for English and expect everyone to follow it.

---

[Kane0]

-Snip-

Your frustration is understandable, but this is the internet so sometimes you gotta know when to fold ‘em I suppose.

There is actually a rule which doesn't involve mind controlling magic.

It is "Druids won't wear metal armour."

It's not the DM saying it either. It's the rules of the game. The DM doesn't need to adjudicate it. It is crystal clear.

A Fnergal won’t Rudisplork.

[eftexar]

---

Your frustration is understandable, but this is the internet so sometimes you gotta know when to fold ‘em I suppose.

* whimpers in corner *

---

And, of course,

A Fnergal won’t Rudisplork,

Kane0.

Fnergal's don't Rudisplork. That's against the Mrkenla of the Zephenskrier. They lagrenf instead. I mean, Obviously. * Phbttbtt . . . *

---

[Addaran]

Those who insist it's a DnD rule don't understand {Scrubbed} human nature.

{Scrubbed}

No matter if it's a lapse of jugement that happen once, it's done to survive/save a life or if it's just an imperfect follower.

PS Yes, not wearing metal armor is an in-game/in-character rule, just like "homeowner in waterdeep pays taxes" and "wipe your feet before entering Helm's temple". That does NOT mean every single characters will follow those rules.

PSS eftexar, they don't answer your question because they are obtuse about it and refuse to see they are wrong.

[eftexar]

I feel kind of sad , Addaran. You simplified my whole spiel, my tldr text, in a single short post. And with such clarity too . . .

No, really, thanks for the support. I took too much time out of my day(s) with this. That and my brain hurts.

The, uh, original reason for this thread was to ask whether DMs leaned more towards Mechanics or more towards Fluff right? Or was it Player preferences? Or, both? Feelin' kind bad for the OP now. Sorry, * checking the first post * uh, . . . Sithlordnergal.

[Kane0]

Fnergal's don't Rudisplork. That's against the Mrkenla of the Zephenskrier. They lagrenf instead. I mean, Obviously. * Phbttbtt . . . *

Ah but good sir I said they *won’t*, not that they *don’t*. You have activated my trap card! I send you to the Dead Zone!

-Snip-

Yes, but beware the forum rules.

[ad_hoc]

Those who insist it's a DnD rule don't understand {Scrub the post, scrub the quote}human nature.

{Scrub the post, scrub the quote}

No matter if it's a lapse of jugement that happen once, it's done to survive/save a life or if it's just an imperfect follower.

Yes, like you said, they are breaking rules.

The difference is that in a game if you break rules then it is customary to not allow you to play the game anymore. Break a rule, suffer the consequence. That's how it works.

What happens to the character is moot because the character is no longer a PC when the player has left the game.

PS Yes, not wearing metal armor is an in-game/in-character rule, just like "homeowner in waterdeep pays taxes" and "wipe your feet before entering Helm's temple". That does NOT mean every single characters will follow those rules.

Druids will not wear metal armour is a rule of the game.

A character expecting to pay taxes is a situation in the game. Characters can break the laws of the societies they are in without breaking the rules of the game. I'm sure that battalion of orcs doesn't want you to kill them, but you are allowed to try anyway.

Just change the rules if you don't like them. It's a simple solution for you. I think you're losing out of course, it's a good rule. That's your mistake to make.

[NichG]

Well, are you going to answer your own question? I, mean, it does have an answer.

I would assume he would risk losing his licence. He would at least have to face a review board. He might even face trial and go to jail. Does he stop being a Doctor? That's a harder question to answer. Philosophically, perhaps yes. Educationally, perhaps no. Even if you don't consider him a Doctor anymore, he still has all his skills as a Doctor. It might just be illegal to use them. Applying Mechanics to the real world, he doesn't suddenly forget to use a scalpel because he broke his oath or "he can no longer be considered a Doctor."

Not sure what you are trying to prove here. I answered your question, no one answered mine.

What happens to a Druid who wears Metal Armor?

I answered this before, and the answer is the same as for the Hippocratic oath: nothing happens.

The Hippocratic oath isn't legally binding. Violating it does not generally mean that the violation will be discovered. The violation being discovered does not generally put a doctor's license at risk. A doctor can freely violate their oaths, much like any person is physically capable of violating any oath that they make. Certainly nothing happens that makes the doctor physically unable to heal wounds anymore or anything like that.

And in the same vein, if a druid puts on metal armor, nothing happens.

But that doesn't mean that the Hippocratic oath is unimportant to the doctor, nor does it mean that the druid's sacred oath is unimportant to them.

If you undertake to play a doctor who has sworn a Hippocratic oath, and portray them violating it flagrantly without a care in the world, then you as the player are rejecting the premise that you have claimed to have undertaken. The universe isn't going to swoop down and punish your character for it, or you, for that matter, but it's still a case of you saying you would do something and then failing to do it. The only thing that will happen is, people may call you on that, and would be justified in doing so.

[eftexar]

---

Ah but good sir I said they *won’t*, not that they *don’t*. You have activated my trap card! I send you to the Dead Zone!

Ahh, no! Curses, foiled again by the hero! The Grrglsnp will still be mine, hero! I will rule them all! Ah, ha, ha! * cough, cough, wheeze *

---

The difference is that in a game if you break rules then it is customary to not allow you to play the game anymore. Break a rule, suffer the consequence. That's how it works.

Hmm . . .

Must have never watched American sports before.

---

Anyway, in response to the OP :

I think whether or not I would go for Mechanics or Fluff, would depend on the game and audience. Some Players just want to fight Monsters and smash stuff. Other's care more about the story and how they fit in it. This being the case, I don't think one is better than other (at least not in every situation).

Personally, though, I prefer the Rules. It's easier to build Fluff around Rules, than it is to build Rules around Fluff. It's also more fun. Especially since I can just let my imagination run wild. Granted, I enjoy making Homebrew and "stat-ing things up". It requires deep thought, especially with the Mechanics.

---

[ad_hoc]

---

Hmm . . .

Must have never watched American sports before.

Not all rules have the same consequences for breaking them.

In hobby games it is customary not to play with someone who breaks the rules. 99% of the boardgames I have played have not specified what happens if a player breaks the rule. It is just assumed that the player loses, is removed from the game, or causes the game to end. I would not play with such a player again as breaking rules ruins the game.

If there are no consequences for breaking a rule then the players are just agreeing to creating a houserule by removing that rule.

So is this where you are at? Discussing what the consequence to the player should be for breaking rules? That's an entirely different discussion though I can't see any other option than to not play with them if they insist on breaking the rules.

[Addaran]

Yes, like you said, they are breaking rules.

The difference is that in a game if you break rules then it is customary to not allow you to play the game anymore. Break a rule, suffer the consequence. That's how it works.

What happens to the character is moot because the character is no longer a PC when the player has left the game.



Druids will not wear metal armour is a rule of the game.

A character expecting to pay taxes is a situation in the game. Characters can break the laws of the societies they are in without breaking the rules of the game. I'm sure that battalion of orcs doesn't want you to kill them, but you are allowed to try anyway.

Just change the rules if you don't like them. It's a simple solution for you. I think you're losing out of course, it's a good rule. That's your mistake to make.

They are breaking in-character rules. Like the character not paying taxes. Not any game rules.

You acting like the player broke a rule means druid are held to bigger standard then paladins, clerics, celestials and demons.

Apparently not druid in the whole history of your world has even fallen that "religion" rule. But some paladins and clerics do fail to fallow their codes/religions. Some celestials fall and become evil, some demons do become good (which might change their physical nature).

You honestly don't see anything wronf with that?

I don't need to change any of the DnD rules. A druid wears a metal armor, nothing happens according to the rules. There's not a single place that say what happens to a druid who wear a metal armor ( no, not talking about his AC improving, i'm talking about consequences), weither it's on his own free will, being dominated, tricked, whatever.
You can decide IC consequences like shuning from other druids, just like when a rogue is caught stealing. You can rule that there's some consequences like losing spells or shapeshift, but that's a ruling. It's not RAW.

[NichG]

They are breaking in-character rules. Like the character not paying taxes. Not any game rules.

You acting like the player broke a rule means druid are held to bigger standard then paladins, clerics, celestials and demons.

It's not the druid that is held to that standard, it's the player.

The class says 'if you take this class, you agree to play a character who won't wear metal armor'. If the player says 'ha, my character wears metal armor!' then the person in violation of the game rules isn't the druid, it's the player. So nothing happens to the druid, but the player has broken their word, and will be treated accordingly.

It's no different than if there was a table rule 'okay, to play in this game you have to agree to play a character who will get along with the others - we don't allow PvP, etc'. If the player has their character stab the party's rogue in the back, its not the character that has broken a rule, it's the player.

[ad_hoc]

They are breaking in-character rules. Like the character not paying taxes. Not any game rules.

You acting like the player broke a rule means druid are held to bigger standard then paladins, clerics, celestials and demons.

Apparently not druid in the whole history of your world has even fallen that "religion" rule. But some paladins and clerics do fail to fallow their codes/religions. Some celestials fall and become evil, some demons do become good (which might change their physical nature).

You honestly don't see anything wronf with that?

I don't need to change any of the DnD rules. A druid wears a metal armor, nothing happens according to the rules. There's not a single place that say what happens to a druid who wear a metal armor ( no, not talking about his AC improving, i'm talking about consequences), weither it's on his own free will, being dominated, tricked, whatever.
You can decide IC consequences like shuning from other druids, just like when a rogue is caught stealing. You can rule that there's some consequences like losing spells or shapeshift, but that's a ruling. It's not RAW.

It doesn't matter what NPCs do.

It is a rule for players. Player rules only pertain to the players who play PCs. 5e is not simulationist like 3e tried to be.

NPCs follow entirely different rules (though those rules are just that the DM decides what they do and what their properties/abilities are).

It's not the druid that is held to that standard, it's the player.

The class says 'if you take this class, you agree to play a character who won't wear metal armor'. If the player says 'ha, my character wears metal armor!' then the person in violation of the game rules isn't the druid, it's the player. So nothing happens to the druid, but the player has broken their word, and will be treated accordingly.

It's no different than if there was a table rule 'okay, to play in this game you have to agree to play a character who will get along with the others - we don't allow PvP, etc'. If the player has their character stab the party's rogue in the back, its not the character that has broken a rule, it's the player.

Exactly this.

Druids won't wear metal armour is a rule.

PCs won't be evil is a houserule.

Both are valid.

(It can be argued that PCs won't fight other PCs is already a rule as the game says that they team up together, though it is not as explicit as the Druid and metal armour)

[diplomancer]

Imagine this situation.

PC "I want to play a Druid"
DM "I will have you know in advance that I strictly enforce the PHB rule. As a druid, you won't wear metal armor, because druids don't do so"
Game begins, party finds a shining magic metal breastplate
PC "Dibs on it! I start to put on the metal armor"
DM " no, still not ready to change that rule"

The table is now at an impasse, and game stops. A long philosophical discussion starts about free will and the meaning of won't. Other players start to be bored and start looking at their phone, losing immersion.

Whose fault is that? Is it the DM's for "controlling someone's character actions for them"? Or is it the player's for insisting that his character's free will supersedes the rules of the game?

What if the DM did not give forewarning (perhaps he never thought too deeply about the rule)? But once the situation appears he says "I don't think you can do that. PHB says druids won't wear metal armor". Player start saying "you are taking away my character's agency" DM "no, the rules you agreed to play by did" player *starts a long-winded philosophical discussion*

Should the DM, to keep game going, just give the player what he wants? Will he (and the other players) have fun playing such a game

[eftexar]

ad_hoc,
My reference to American Sports was to point out the Absurdity of your Imposition. Who says it's customary to play hobby sports the way you are indicating? You? Is this entirely based upon "your Experience(s)" and no else? Or is it only based on "your Experience(s) and anyone else who agrees with you." I'm not accustomed to DMs kicking Players out for disagreeing with them. If the DM did, he would kick the whole group out. Who are you playing with, Gaming Nazis?

I'm not discussing consequences for the Player breaking the rules, but the Druid not abiding by an EXPECTATION. Addaran is right when he indicates this. You are confusing the forest for the trees. The Druid is not the Player. The Player is pretending to be the Druid.

Nich_G,
You are equating that, "Because I agreed to play this Game," "I agreed to play it as Nich_G interperets the Rules." The Druid might have, arguably broken the "Rule", but equating Character behaviour to Player behavior is a FALLACY. Roleplaying is all about playing "as if" you were the Character. It is not "you are the Character."

The Player hasn't broken their word. They might not agree to the "Rule," which you keep ignoring might not even by one by the English definition, simply because they are playing the game. It's not Scrabble or Uno for Gygax's sake, it's NOT JUST A BOARD GAME. IT IS A ROLE PLAYING GAME. It serves both as a Game and a medium through which to tell a Story.

ad_hoc,
So Player's must "Play the by the Rules," but NPCs don't? Why? Because you said so? Because the DM can do whatever he wants without any regard to his Players' Expectations, but the Player must meet ALL of his expectatations. You are extended the Rules that give the DM freedom to be flexible, beyond what they were intended to do.

And "Druids don't wear Metal Armor" is an ASSUMPTION or an EXPECTATION. {Scrubbed}

---

Edit :

Spoiler

Show

Quote (Diplomancer) : Imagine this situation.

PC "I want to play a Druid"
DM "I will have you know in advance that I strictly enforce the PHB rule. As a druid, you won't wear metal armor, because druids don't do so"
Game begins, party finds a shining magic metal breastplate
PC "Dibs on it! I start to put on the metal armor"
DM " no, still not ready to change that rule"

The table is now at an impasse, and game stops. A long philosophical discussion starts about free will and the meaning of won't. Other players start to be bored and start looking at their phone, losing immersion.

Whose fault is that? Is it the DM's for "controlling someone's character actions for them"? Or is it the player's for insisting that his character's free will supersedes the rules of the game?

You say "Enforce the Rule," but you haven't established that the "Rule is a Rule" and not just "Fluff and Expectation." There is "no Rule change" in this circumstance! {Scrubbed}

Further, you are imposing the OPINION that "a Player is insisting his Character's free will supersedes the rules . . ." Also not true. Not only have we established, as you haven't presented anything that has indicated otherwise (again, "I said so" doesn't count), that it may not be a Rule, but this was never said or even inferred for that matter. The DM should NEVER let the Game get to that point in the first place.

Assuming the text is a "Rule", and "in absolute" at that, equates to a DM, who thinks "the Character Won't" means " the Player Can't." You are using a possible Rule, one that breaks game immersion and contains YOUR specific interpretation of it, to DICTATE your own view point. This is not a House Rule. This is not a Ruling. You are not being a DM. This is just you wanting CONTROL, more than how much you care about your Players enjoying the game. You are willing to use any excuse, invalid or not, to KEEP CONTROL.

---

Edit :

What if the DM did not give forewarning (perhaps he never thought too deeply about the rule)? But once the situation appears he says "I don't think you can do that. PHB says druids won't wear metal armor". Player start saying "you are taking away my character's agency" DM "no, the rules you agreed to play by did" player *starts a long-winded philosophical discussion*

Should the DM, to keep game going, just give the player what he wants? Will he (and the other players) have fun playing such a game

See. CONTROL. You are equating / implying "all Players, except the 'obviously' disruptive Player, agree with the DM." Also NOT TRUE. You are forcing your perspective on other people. And you are dictating the discussion by PLACING WHY YOU THINK, THAT I THINK, SOMETHING. YOU ARE NOT A MIND READER! And this only became a "long-winded philosophical discussion," because you refuse to see any other point of view, to the point that philosophy is the only way to get you to actually think for a moment!

And it still says "Druids WON'T wear Metal Armor." Saying the Player "CAN'T wear Metal Armor" is something the DM can House Rule. This limits the Character, not the Player. It places an expectation that is REASONABLE. Saying "Druids WON'T wear Metal Armor" is completely different. WHY WON'T THEY WEAR ARMOR? You can't answer that with BECAUSE THEY WON'T WEAR ARMOR.