I'm participating with my game in this Next Fest and I don't really think this is much of a problem. The amount of games presented doesn't seem significantly higher than last Next Fest. Games that are good get boosted after 2 days (first 2 days everyone gets featured randomly) so low quality AI slop won't get much of attention. And the way they check if a game is popular is wishlist count and player/install count as far as I understand. I don't think low quality slop will get much of boost, and if it does it probably is deserved unless the wishlist count/player count gets botted somehow, but I haven't really seen this happen but who knows. For most people I think it's best to wait until after the second day to see which demo's are worth checking out, there won't be much AI slop there.