I think my main issue with your original post is that you expressed what you've achieved as a generality and not as the result of your specific, active curation

I think my main issue with your original post is that you expressed what you've achieved as a generality and not as the result of your specific, active curation of your Mastodon experience. That you can achieve warm, cozy, and non-toxic with active curation is not something I'd dispute. But I'd maintain that experience is not the default experience and I'm not sure that's so different to what you could also achieve with Twitter either (I could be wrong here, been along time since I used Twitter). To be fair, I'm not sure that anything trying to have the reach and be of similar purpose to Twitter can escape some flavor of Twitter's fate... whether that is leftist or rightist dystopia being irrelevant to the point. And to be fair I've even toyed with the idea of setting up Mastodon instances (though probably using different server software) focused on strictly civil/professional discussions as part of the rule set. But of course this leaves most of the "federating" part of the equation off the table and leads me to my next observation. The only social networking that I've found that is genuinely warm and cozy, by default, are some of the Discourse communities. They are absolutely small, disconnected islands of community, but by being topical and smaller I think they avoid the toxic by default characteristics that broadly generalized communities devolve into. Of course, Discourse communities can be built around toxic content, too, but you just don't sign up: what you see is what you get. I think this more topically focused social media is really the best way to avoid the cruft compared to the open community approach.