So it’s basically just twitter but without the nefarious overlord?
It's heavily inspired by twitter, but with people who didn't like ads and did want to keep LGBT people safe from harassment.
Also there a great love of privacy protections and cooperation, so there's many other instances some of which are optimized for other use cases and they can all interact.
So there's pixelfed which is instagram inspired, but you can interact with people posting there, from mastodon and it mostly works fine.
There's also bookwyrm that's designed for sharing what you're reading.
