The tOSU board I frequent has a feature where you can upvote/downvote posts. Seems like a lot of boards have this, actually. If a single post receives enough downvotes, it gets greyed out - difficult to read and easily identifiable as a shitpost. If a poster gets achieves enough net downvotes, they can't start their own threads. If they get enough more net downvotes, they're banned.
Definitely imperfect, but seemingly pretty good way of allowing the community to police itself. I think in ~5 years, I've seen 4-5 people, mostly trolls from other fanbases, achieve the permanent ban. Not sure if it would work here, but it's certainly a much more positive/friendly place. And they're a bunch of Ohio mouth breathers...