I think you hit the nail on the head with "Mastodon feels like rolling back the social media clock to the pre-Facebook days, when there were smaller and more focused communities on message boards and such. BlueSky, on the other hand, feels like rolling back to Twitter from about 10 or so years ago."

Of course, I believe strongly that BlueSky will end up following the same path as Twitter, too. At some point, they will need to monetise, and that will mean ads. And that will mean "rewarding" engagement bait, which means more anger. And of course, the Nazis will show up because they will get bored with having no one to shout at on Twitter once all the liberals have left. And so it goes.

I think there's also an unreal nostalgia for pre-Musk Twitter at work too. Musk made Twitter worse, but it was already bad. Harassment wasn't invented by Musk, and if you were trans, or gay, or just had a conscience it could easily become very toxic. I had friends who fell into TERFdom, and others who spent their entire lives on Twitter in a way which wasn't even vaguely healthy for them or other people.

Mastodon is seemingly pretty impervious to that because – and this is the bit that people often miss – the server is the community, at least for people on smaller servers. Being able to connect to other people on other servers is a bonus, but it doesn't have to be everything. That's why people who rail against "servers being able to just block big servers" just don't get it.

There's also a huge amount of Highlander thinking at play: "there can only be one" social network. The number of times on BS and Threads I've asked people who post attacks about Mastodon and I've asked people why they just can't enjoy what they enjoy and let other people have what they want... and there's never a good answer.