Yeah, I absolutely agree that itch.io should have 1 concise warning when downloading for the first time implemented, the same way as the warning you get when opening an 18+ game page, and that should be enough, prioritized somewhere among the optional donation window.
Having extremely active trusted users who play games become moderators who have to check uploaded games in queue to approve it's safe to download could be cool, but probably unrealistic, the biggest flaw being that some games will never be published because of just how many there are uploaded every hour