Personally I only use Hive for Actifit posting, maybe there's a way to differentiate between transactional users and those who are deeply invested in the war. (And saying the word "invested"... maybe just checking someone's Hive Power can be a rough estimate for how strongly they care about Hive).

That's probably worth looking at. I suppose it could also look for STEEM to HIVE transfers in the wallet history. I've also been thinking about using whitelisting to address this. I even had to put a specific exclude filter on an account that has been inactive on Hive for more than 4 years because the account owner was so aggressively hostile to Steem at the time of the split. There just doesn't seem to be a 100% way to handle it. In the long run, I think whitelisting coupled with decentralized operation would probably get the closest, but multiple layers of checks are also good.

I wonder if there's a way to more easily acquire knowledge of what known-bad content is out there.

IIRC, for a while before 2020, Cheetah would lay down a 1% vote on content that it thought was plagiarized, then other curators could disregard the post if they saw the cheetah vote. I never thought Cheetah's plagiarism detections methods were great, but the signaling method was good. That could be useful for both plagiarism and AI detection.

We also have the current method where community mods/admins post their findings in a comment. That feels spammy to me, though, and it makes automation more challenging since natural language processing would be needed.

I don't know exactly how this can play into the social dynamics, but one thing that perpetual-rewards-via-beneficiaries does is bypass the curation rewards on the original post.

This is a good point that I hadn't thought of. I'm also not sure how how that would influence the incentives, but it bears consideration.