I hint at this a bit in runyourown.social, but "UX-based onboarding" is a horrible compromise that social-media-at-scale like Facebook has convinced us all is "best practice." It makes sense if you are one company serving millions.
I think this fediverse moment we are having is as good a chance as we are going to get to examine these assumptions, and experiment with throwing them away and trying very new (or very old!) things.
Stacy Horn's "Cyberville" is a memoir about running a New York City based BBS that ran through the 1990s and early 2000s. She talks about having phone calls with new users and walking them through what they need to know about the place. Hugely influential on my thinking.
https://www.grandcentralpublishing.com/titles/stacy-horn/cyberville/9780446572064/
(Many thanks to @theuniverse for turning me on to this book btw)