That seems a lot like arguing semantics. Do you have any example of a creature or state of a creature to which implosion, by way of its mechanic (crushing) should not apply, but does?
If you read the thread referenced above, you will note that "death effects" are NOT spells with the [death] tag. That would be redundant. Death effects are supernatural effects that, according to their description, are death effects.
And how does Power Word: Kill kill you? It is quite apparent that it attacks your life force. And it is a great example of why Death Ward has nothing to do with "save or die", because Power Word Kill is blocked and is not a SoD.
I am sorry but this is nothing but semantics. All of the spells you listed do theoretically infinite damage if the target can be affected by their mechanic. Implosion is no different. You can either ignore the effect description altogether, or take it into account. You cannot ignore 90% of the effect description and rely solely on the last 2 words. That is not how you interpret a text, as I am sure any lawyer will attest to.
In fact, I coul make the same argument for say cloudkill, as cloudkill states "These vapors automatically kill any living creature with 3 or fewer HD". The immunities are in a different sentence, just as they are in the Implosion description. By that logic, cloudkill is a death effect.
No, but the term "death effect" is specifically spelled out in several abilities that attack your life force. This is presumably the case to make clear which abilities allow raising and which do not.Does anything in the rules draw any connection at all between the [death] descriptor and "death effects"?