Do they need to approve each and every instance manually? I thought it would happen automatically as soon as someone is trying to subscribe to a "channel" of another instance. No?
I'm not familiar with the exact process yet. But doesn't that mean if you wanted to run an unfederated instance, you'd need to manually block every other instance there is?
That's how I understood it. There is maybe a way to blacklist everything (like using a wildcard) or disable federation? I don't know. Maybe I will try to run my own personal instance just to learn how it works :)