The continuing strong market preference for 3E/PF shows us something important, I think, about general tastes in the current RPing market:You inevitably don't think "system matters" so much if your answer to most issues is "GM hammers/forces game/story into shape"
(1) stat + skill as the essence of PC build retains a high degree of popularity, it seems at least in part because of its apparent mapping to both the nature and the nurture aspects of a given character's genesis;
(2) "customisation" of characters is as important as an element of colour as it is in relation to action resolution; perhaps even moreso;
(3) hit point combat resolution retains a high degree of popularity over death spiral combat, but with rocket tag magic seen as a type of permissible override provided its on some sort of leash;
(4) GM force retains a high degree of popularity over metagame mechanics and overt social contract around genre, scene-framing etc, as a way of making the game hum along.
(2) "customisation" of characters is as important as an element of colour as it is in relation to action resolution; perhaps even moreso;
(3) hit point combat resolution retains a high degree of popularity over death spiral combat, but with rocket tag magic seen as a type of permissible override provided its on some sort of leash;
(4) GM force retains a high degree of popularity over metagame mechanics and overt social contract around genre, scene-framing etc, as a way of making the game hum along.
(1) and (2) also seem connected to "immersion" as a goal of play, which retains importance. (4) also seems related to this, and among other things also seems to act as a brake on the potentially anti-immersive consequences of (3).
At least, that's my take. The Forge idea, that we could make (4) redundant by inventing new systems that would hum along on their own if only everyone did what the system asked them to do, seems to have failed.