Each instance has its own community, its own zeitgeist which reflects a facet of your personality. Specific interests, mindsets, etc.
On twitter, this granularity is absent. You either follow someone entirely, or not at all. Here, you follow parts of a person.
You bump into someone on a.weirder.earth who posts cool things on conlangs. Later, you find them on wandering.shop, posting cool stories. Then, you find their beefs on mastodon.social to be too abrasive for you.
Guess what? You'd never have read their stories and stuff on twitter, because there you have to drink the entire tub of bath water, baby and all.
Basically, you're increasing the surface area of your soul, in a way which actual humans do in real life. You befriend parts of people, to various degrees, and very rarely find someone whose every facet is equally interesting.
@Pookleblinky Instances as G+ Collections?
@Pookleblinky Except I'm not sure that most people will be that granular. People will probably post stories about their day in the conlang space, politics-adjacent things in the social space, etc. I think people often think of themselves as one unitary person, so may not partition by subject like that.
It might happen a bit more if there wasn't the clunkiness of switching instances. Maybe a dropdown in the text box of "Where do you want to toot this?" would help?
You may follow their politics on foo.bar, their healthstuff on baz.quux, but not even know about their AD on fibble.wobble.
"Follow" becomes a spectrum. There is a greater surface area for converging interests.