We’re a loooong way from games that are completely generated by AI so I wouldn’t worry about that.
However, if we’re talking about games that use AI-generated assets like sprites and music, then those are much more likely to flood Itch.io in the near future. If you look at the new assets published on Itch.io, you’ll see not a small number of them being AI-generated, I’d say around 25-30% of new assets are made with, or assisted by AI.