Mastodon has been better than I expected after the first Twitter exodus slowed down. Much less noise than X/Twitter. The protocol may turn out not to be scalable, but it's very much alive.
It's like a compromise between forums and twitter, and there are some great smaller communities out there. When the curation and moderation are good, and the community has a solid purpose, you get gems - quite a few mastodon gems out there.
At this point, it isn't clear why federation is in there at all. The "forums, bit twitter" concept does produce nice places, but federation seems like a net negative for that.
Federation is good if you want to stay within a community but also have a chance to interact with others.
I.e. you mostly care about technology foo but occasion delve into epic poetry, and it's nice to interact with both footech.social and epicpoems.read. Also, being able to consume personal publishing (blogs!) from within the same app is quite nice.
The steelman for federation is that email survived the rise of the big platforms despite no-one owning email, so making other applications follow the email model means they too could be free from central ownership.
Isn't one a subset of the other? A system with federation must have multiple instances, but a system with multiple instances doesn't need to federate (in the sense of information passing between independently managed instances.)
Yes. My original question was whether federation is necessary for the kind of communities Mastodon serves, not whether the web must have multiple websites.