@datapup@mastodon.social just kinda box it in there on the side. you can do all kinds of jank shit. on diaspora (speaking as an end user, mind), profiles are sort of cloned over into the jabber instance so everyone on a given server has a profile, contacts populated by those diaspora contacts on pods that also have it. it has another DM system, also, but being built on top of salmon instead of gnusocial there's inherently more control over your streams so it wouldn't fly here.
@datapup@mastodon.social in my experience, gargron doesn't take criticism well. my first interaction with him was asking about privacy and his response was to tell me privacy isn't possible in federated social media which, coming from other fednets, i knew to be completely untrue. i left for months after that, didn't see how the rollout went.