[TheOtherHobbes]

That doesn't work, because posts with zero upvotes get the same screen space and framing as posts with 25k upvotes.

This is an editorial issue, because those upvotes are decorative. They suggest a post has more reach and engagement, and perhaps is more entertaining. But not that it has more objective credibility - which is of course a reflection of Facebook's preference for promoting the former over the latter.

Voting isn't the answer. There may not be a community-sourced answer, because any system you imagine can be gamed by any more or less organised adversary.

The only workable solution is manual moderation with some attention to tone and content, and the banning of those who consistently troll.