It might be too early to tell. SN does of course have a different incentive structure to Reddit, Twitter, etc. where upvoting content has a cost, so things might not play out in the same way.

I guess you could introduce the equivalent of a downvote button. I pay 100 sats to deduct 100 sats from a post I dislike, and the sum of that is redistributed via the community pool.

Raising costs to post and introducing staking seem like interesting ideas too. I can see that being useful for spam prevention.