Right now experimenting with a "demote" button that people are encouraged to use on: disinformation, misinformation, propaganda, spam, and slop.
Communities' default feed is just chronological, but it also has "Most Active" and "Most Recent Activity". Right now, Demote knocks things down the "Most Active" feed.
Eventually, a high enough percentage of demotes would result in posts being removed from public feeds. A second, higher threshold, would result in it being removed from all feeds.
Demote usage would be moderated, and removal thresholds could be appealed to the official moderation team. Users who abuse or misuse demote would lose the privilege.
It's an experiment and we'll see if it works. It's also really early. But the thing that Communities is doing differently is that the users will ultimately be in control through democratic elections of the board. And I expect moderation to be a frequent and recurring issue in elections. (You know, if the whole thing gets off the ground at all.)