We still haven’t really sussed out whether the dominant model is going to be general or specific focus instances, or even brought whether niche boards want to just be in charge of the content and not the users, since your credentials are good everywhere you’re federated.
Right now your ‘all’ feed is a combination of all the various places users on your instance have trawled, but they’re not totally the same everywhere.
We could see curated instance feeds with some instance muting from admins that make it function like a public RSS, per user even if it gets that granular. Skies kind of the limit once you understand it’s limited to insecure communication, the most anonymity you have here is in a crowd.
I mean it predates a lot of the pervy anime, but Usenet looked the same at the start with lots of Unix/computer boards and an alt.
Computer enthusiasts gonna enthusiastically talk about computers. People who pick up and move to a new platform are likely to be united around being technically competent enough to get there first, and everything else second.