This Gunslinger example is interesting and a bit surprising - people are happy to play PF and just ignore this ability if they don't like it, but can't do the same with D&Dnext?
Yes, I would be less likely to pick up an edition that doesn't include the options that will let me build and play the sorts of characters I am interested in (whether as player or GM).
All these complaints are framed within a presupposition - namely, of a type of process simulation in mechanics - that I (and, I suspect, some others who don't object to DoaM - such as @Hussar and @TwoSix , based on their posts upthread) do not accept.
GWF does not represent training or skill. It occupies something like the same space as the barbarian's rage - it expresses fierceness, determination, resolution, inevitability.
And the fact that the mechanical resolution of a successful attack roll is not affected by the ability does not mean that that fiereceness, determination, resolution and inevitability cannot be incorporated into the narration of a hit. In fact, I would expect such incorporation to be fairly typical.
Because that ability isn't built into the Gunslinger and there are plenty of alternative abilities that replace it.