Many (not all, obviously) who would have bought it had it appeared last year won't now.
Why?
1. No hype for the game, and any attempt to hype it anywhere will be shot down by the existence/reports of MHW
2. XX was never a game MH fans REALLY wanted. Regardless of hype, game will feel even more outdated and irrelevant than it did before, after MHW.
So unless you are a Western MH fan who absolutely must get his MH fix no matter what, you won't buy XX now.
I have 600+ behind me on MH3U, and won't touch XX with a pole now (would have bought it last year though). If a new MH game comes out to the West at some point, I will consider it then.