[NoGravitas]

My only thought is "scale only through federation". It's impossible to moderate the content of a billion users. It's pretty easy to moderate the content of 1000 users. And if you're moderating the content of 1000 users who mostly come from an actual community (physical or subcultural) that shares the same values, you don't have to have your moderation rules enforced worldwide to the lowest common factor of different value systems, or by outsourced wage slaves from a different culture without any context.

Source: I'm a moderator on a Mastodon instance with about 1000 users (connected to the larger Fediverse of about 2 million users). We've got 5 moderators, and we respond to reports (either by or about our users) promptly and well. We don't have to police the behavior of the whole Fediverse (just our users), and we don't have to protect the whole Fediverse (just our users).

[aeling]

I haven't used Mastodon, but this is kind of the reddit model, right? Obviously some subreddits are >>> 1k subscribers, but they typically scale the quantity of moderators up accordingly.

Do Mastodon admins share common blocklists or anything? If a bad actor decided to start posting offensive content to random instances, I assume you can ban that {username | IP} from the instance used by you and your users, but would they then be able to just iterate through the other n Mastodon instances? Is there anything in place to prevent them from creating a new account and repeating ad nauseam? (not that there is on Facebook, necessarily)

(I don't know anything about Mastodon, which I'm sure is obvious from some of my questions - if they're incoherent in the context of Mastodon that's totally fine)

[NoGravitas]

It's not very like that – subreddits are all on one server, but posts only appear on one subreddit, whereas Fediverse instances are separate servers, but posts propagate between different instances.

Mastodon instance administrators have the ability to block whole instances, and this is usually done because of bad/nonexistent moderation policies. There is some sharing of instance blocklists, more as a matter of convenience than of policy.