This writeup is useful for backend engineers: https://atproto.com/articles/atproto-for-distsys-engineers

The simple answer is that atproto works like the web & search engines, where the apps aggregate from the distributed accounts. So the proper analogy here would be like yahoo going down in 1999.

This is a fantastic write-up, thanks for sharing!

Google and MSN Search were already available at this time. Also websites used to publish webrings and there was IRC and forums to ask people about things.