It’s not a terrible idea to create a network of interest-based Mastodon servers, but there’s an easier way to do the same thing.
Create one server that can host groups. Allow people from other servers to participate in those groups.
This is what I do with venera.social, and it’s what I will do with calckey.social once Channels start federating.
RE: https://social.coop/users/jsit/statuses/110350726425293860
One thing to keep in mind is that the technology behind #Fediverse , #ActivityPub , scales in resource use with primarily by number of instances, not so much number of users.
To put it a different way, it’s a much larger load on the system to add 50 instances, two users each, than to add one instance with those same hundred users.
Be careful pushing for far expanded numbers of instances, as the resource use to do that might not be sustainable.