Fediverse

That's not to say that social groups putting limits on association is _always_ a good thing, just that it's a necessity for maintaining a healthy group.

All the examples you provided were infrastructure, not social communities, so I think it’s a poor comparison.

I find it very hard to draw clean lines that categorize email as "infrastructure" and the modern fediverse as "social communities". There is a clear email-based precedent for Lemmy in usenet, for Mastodon in email lists. I struggle to think of any activity we perform in the fediverse that doesn't have a fairly close analog that was powered by email.

The thing that makes email "infrastructure" is not how we use it, but rather how we rely on it. In the early days of mail ecosystems, it wasn't always possible to communicate across providers. Email became infrastructure because the ubiquitious interconnection it provided was so useful. If the fediverse is successful, I would expect it to become infrastructure in a very analogous way.

Even larger constructs like cities or nation states.

In those examples it’s clear that limiting association is commonplace and healthy.

It don't understand this argument. Nations do restrict travel, communication, and trade to other nations. The costs of doing so are enormous, and nations that do so excessively are generally regarded as totalitarian regimes... not something to be emulated.

Comparisons to clubs and friend-groups break down in usefulness when we're talking about a group of three hundred thousand of our closest friends, growing at 5% to 10% per day. When these kinds of systems scale to infrastructure size, they become more like governments which I addressed above.