@koteisaev yes. Fediverse is designed to give everyone a megaphone. Some people want to use the megaphone to have private conversations. Quite a strange idea. Same for e2ee encrypted messengers some will use as a megaphone (making rooms with thousands people).
I agree a protocol between x people to automatically negociate a chatapp to dm would be cool. Or maybe integrate xmpp, there is a bluesky dm implementation based on matrix. Reuse may work best