The designers of activitypub know that it will never work:

"A fundamental flaw occurred in our design; we over-valued the role
that instances should play altogether.
While there is nothing wrong with blocking an instance or two, the
network effect of having this be the foundation is re-centralization."

from: https://gitlab.com/spritely/ocappub/blob/master/README.org

Federation, by design, leads to abuse, which leads to moderation of abuse, which leads to everyone getting tired of moderating it, throwing in the towel and consolidating into the next web2.0 #activitypub #mastodon #mastodonsafety

Lots of people on #twitter complaining that they are put off by the #mastodon sign-up "choose an instance based on your interest" page, and they are completely correct. It's bad design.

"Furthermore, it doesn’t even reflect human behavior; few people
belong to only one community.
Alice may be a mathematics professor at work, a fanfiction author
in her personal time, and a tabletop game enthusiast with her friends."

So many gems in this readme.