@compostgoblin There were several other protocols such as OStatus, Diaspora, and Zot prior to ActivityPub. Mastodon originally used OStatus, and switched to ActivityPub later. A lot of platforms are older than Mastodon too.

@compostgoblin Some of the earliest platforms included StatusNet, Diaspora, Friendica, Red Matrix/Hubzilla, etc. All are much older than Mastodon.

Usenet is 45 years old, and we’ve been living through an Eternal September for over 30 years.