Maybe but the straight up incentive of tricking someone on your site wont be there, as well as a clear set of tactics. I feel like it would be as challenging as DDOSing cloudflare. It just might be too expensive to do outside of countries or large corps.
I'd imagine that it would be similar to the mechanism that is already used by existing search engines like Google, and people like you & I. So a combination of reputation & heuristics.
Generated content as the new blogspam, in turn needing to be filtered out for training the next generation of models.