The response? Houserule it. So what if technically the weakling has a 30% chance of out arm-wrestling Hercules? Obviously Herc should win, so just houserule that he always will. Or with Fighter's lack of ability to do anything? Houserule that they can. That's not how good games are designed.
The good thing about rules is that they give the players firm ideas about what they can and can't do. The bad thing about rules is that they give the players firm ideas about what they can and can't do.

All RPG rules come with an opportunity cost. That cost is how your players think in a situation. 3.X brought in lots of good rules, but it also lost that rich ingenuity that was the hallmark of previous editions.

What is it that makes a good D&D game? Is it "good rules", or is it "player experience"?

In my opinion, RPG rules are best when they bring a situation to life in such a way that your players make rational, if not downright cool decisions. RPG rules are worst when players don't realize that they've happily locked themselves into boxes.