Apparently it’s part of the new bluesky web client which just launched. I think there is a tricky distinction that needs to be made between the stuff bluesky hosts, their web app, and the protocol and PDSs.
It’s fine to have policies about your app, and your PDS (relays in nostr parlance), but not ok when those are run for the protocol. The TOS we’re linking to is for the web app, but it’s not going to be clear to users.
