But it's not a social network. There's no public posts, there's no leverage-your-friend-network aspect. Messaging platforms aren't social networks (e.g. Slack isn't a social network). File storage/sharing platforms aren't social networks. The only social aspect here is following other users and seeing who they followed/are following them, but that's just a trust thing, following someone doesn't e.g. expose you to posts made by them.
Huh, I didn't know about --public. That's interesting.
But that doesn't make it a social network. If Keybase had a mechanism to follow a bunch of people and automatically syndicate all of their public posts into a single stream that could be consumed by a desktop app, then this would be vaguely Twitter-like. But it appears that you have to manually query every individual user whose public posts you want to see, which doesn't scale to automatically following lots of users, which means this feature as-is isn't going to be used to clone Twitter.
