When browsing, you absolutely need to turn on the No-AI tag. This filters out all everything that has disclosed AI usage, and everything that hasn’t filled out the AI disclosure. Unlike most other tags, this does not filter out assets that don’t have the tag in its tag list. The AI disclosure tags are special that way. If it’s too much of a pain to turn on that tag each time you browse, try bookmarking the browse page with the tag already selected. There, problem solved. Unfortunately this does not work with text search because there is no way to combine text search with tags.
Actually, itch is one of the very few asset stores I even bother with anymore, precisely because it makes it relatively easy to filter out AI slop. Most other asset stores I tried have don’t have AI disclosures at all.