@ewok

Yeah and the other part of that story is that when you set the privacy for your post, your instance still sends it to all of those other instances just with a little note saying who it's for, again basically politely requesting that the other instances don't share the post outside of the target recipients.

But same thing, there's no actual way to enforce that, so other instances are completely free to share private posts with everybody.

The system didn't have to be designed to work that way, but it's part of the design where it's not really decentralized but rather centralized among the instances. There's a lot of trust between instances, and I would have preferred to put users at the top of the hierarchy.