Is it any service that includes the ability to federate? If so, are Matrix/XMPP/other non-ActivityPub services part of the Fediverse, or does Fediverse really just mean ActivityPub?
The context is wanting to promote a Matrix chat room on discuss.online: #online.discuss:discuss.online (see post). Does it belong in Lemmy communities like this one, !fedigrow@lemm.ee, etc? Or does it not count as part of the Fediverse?
I think that ATP and nostr are sometimes included as part of the Fediverse because they both have bridges that allow connection. Without the bridges they’re isolated.
ATP still requires millions to host a relay https://www.theverge.com/2025/1/13/24342799/free-our-feeds-social-media-ecosystem-at-protocol-bluesky