Thanks for the explanation.
If a huge number of "laypeople" flocks to Mastodon, it's very likely that the users will be clustered around one or small number of "major" servers. So basically the admins of that server will become the de-facto moderators of discourse, it sounds like. Is that a reasonable course of events?
Or will the idea be more like "lefties should go to $SERVER1, righties to $SERVER2" and then the two servers don't federate with each other because they find each other's content distasteful?