It works like this:
Western RPGs got HUGE, so everyone cast aside the classic RPG styles to jump on the Western RPG bandwagon. Turn based? Tactical controls? Bah! Those are worthless, people want fast paced, in their fact action in an imersive world!
And for a while, that was true... But now, Western RPGs are a dime a dozen.
Morrowind
Oblivion
Fallout 3
Mount and Blade
Two Worlds
Fable
Fable 2
NWN
NWN2
Silverfall
KOTOR2
... I know I'm forgetting some, but I don't know which :)
But they are still being produced, because RPG players will buy them, even if they're not their favorite style of game, and game companies are just like movie producers. They will make what they know will sell.
It takes a company with balls to break the mold (or go back to an old mold), and if they take off, well, then the other companies will follow suit.