Eugen Rochko is the CEO of Mastodon — the open-source decentralized competitor to Twitter. It’s where a lot of Twitter users have gone in our post-Elon Musk era.
The idea of Mastodon is that you don’t join a single platform that one company controls. You join a server, and that server can show you content from users across the entire network. If you decide you don’t like the people who run your server or you think they’re moderating content too strictly, you can leave and take your followers and social graph with you. Think about it like email, and you’ll get it. If you don’t like Gmail, you can switch to something else, but you don’t have to quit email entirely as a concept.
Activitypub groups are nothing new, they have been used in Friendica, Hubzilla, Peertube and Lemmy for years. I described how it works in FEP 1b12. Mastodon decided to create a different implementation which isnt compatible with any of these.