@pbrane perhaps I was unclear. I see Sigmoid.social does have a stated reason for existence and isn't just a boilerplate-copy of upstream Mastodon. That's great. I don't know if you have a hand in its foundation, or whether you're "just" a member of the community, but you being on Sigmoid means you have a home community. You don't consider it's "local tab", as you put it, to be of value, but that's part of the problem, actually.
And what of Mastodon.world, Mastodon.cloud, (the no-longer-) Mastodon.lol, or indeed even about both Mastodon.social and Mastodon.online? What do they stand for, other than "we run Mastodon"?
Indeed, you can as the same of mas.to, where my more active account is hosted. But not of this server, because this one's reason for existing is that it's mine.