There is always a distinct abundance of "trippy" games in these competitions. This list has "Track not found?!", "FourFold", "I want to Google the Game", and my favorite "CHOCH". I think it has to do with lack of resources pushing people to abstractions, but people more knowledgeable about these things can comment on that. There is a distinct lack of trippy games in the main stream, I am not a gamer but whenever I come across these small games I always wonder how it will feel like if this was a full fledged game. The last one I remember is perhaps Braid with its time travel (again, not a gamer, very out dated info) but its graphics are very normal.
This is a great point - but you have to remember the money is what dictates games that go "mainstream". Companies like Activision, Blizzard, and EA are going to push out something that has low-risk, high reward (Call of Duty, Assassins Creed etc.) rather than push the medium of games forward.
They'll leave the interesting "games as an art form" type idea to indie devs, and once some idea or concept has broken mainstream, they'll snatch it and tag it to a well known IP (see Battle Royale + Call of Duty) and call it a day
