"There was a cool feature in GNU social called groups that has never existed on Twitter or on Mastodon. A user can register a group on their server—for example there was one about gardening called “!grow”. If you subscribe to the group and then put “!grow” in one of your messages, all the other subscribers see it in their home timeline. It’s similar to subscribing to a hashtag except the group’s creator can moderate members.
...
It’s kind of fascinating to me that this feature wound up in GNU social even though they didn’t have solutions for long term management. It enabled some cool interactions. It caused a bunch of consternation when things went wrong. Users bumbled their way through.
Is it a good design? Eh, probably not. I imagine that’s why they’re not supported in Mastodon."
Obviously the big drawback would be plunging “engagemrnt” and slower growth. I think it would be healthier. If you’re a wallflower, you find your groups, if you want to spout off, you join those groups... if you want miss manners, you join hers, if you want sailors, you join theirs.