Here's my take on Witcher's performance that has fuck all to do with SFF. There's three scenarios I find plausible
A) New Vegas got hit with the same 'Bethesda bad' stick that Fallout 4 and Skyrim got hit with, and God of War's number on it wasn't as good as we thought. I can't imagine it got hit THAT hard because New Vegas is put on a pedestal by the 'Bethesda bad' people, but I can buy it still hurting from the blowback on the brand.
B) There was speculation that the massive success of the Switch may help Nintendo across the board; maybe that was true and Mario Galaxy 2 is better than it was in 2015. I waver on this one a bit because that would make Stardew Valley REALLY good relative to all the other indies, but it's possible.
C) Rally spillover from Reddit is artificially inflating Witcher's number, because Witcher will be THE game to benefit from any Reddit spillover because that website will sacrifice a newborn infant on the altar of Geraldo.
Is this C point true, because i think its just a meme at this point, i have never seen any proof for it except over-exaggerated over-emotional theories.