The #Diaspora project is what it is, but I really like the Diaspora protocol separation between authorship and ownership. In this model, the original poster is the rightful owner of all the replies that gets published in the thread they started. They are responsible with distributing replies to the original recipients, whether they follow each other or not, and can even delete replies as they see fit, and the deletion is propagated as well.

This avoids the current #Mastodon behavior where in a Follower-only conversation, each individual recipient may only see the original poster's replies to other people which own replies they didn't receive because they aren't following them.

With #ActivityPub, is there a way out of this half-private message, half-group conversation situation where only the original poster has a comprehensive view of limited privacy threads?

I wanted to publish a personal posts to my mutuals only which #Friendica allows, but I realized that any reply to it might not be visible from the other thread recipients, which means my own subsequent replies would be confusing for anyone's not directly following the person I'd reply to. And this has prevented me from actually writing my post.