An interesting point of view for sure.

Looks like they slant toward overly difficult, Souls-like games.

I'd say that there definitely is a correlation there, but probably not causation. Game of the Year is generally awarded to games that had the most impact on the video game "ecosystem" at large (I hate calling it an "industry", but better words are hard to find). And it seems to me that the challenge/difficulty aspect has always played an important role in the history of video games, dating at least as far back as the arcade cabinets from the 80's.

Given that most modern games at least contain elements of challenge, and given that it is what is expected by the public at large, I guess it makes sense that these games end up being featured more.

I guess what I'm trying to say is, non-challenging games are still pretty few and far between, and they tend not to align with the factors that make games very popular among the bulk of the public.