If the descentralization of social networks continue, we will have to prepare for the eventual rise of the instances wars, where people will start to fight about which instance is better and which one is weird to be in and so on, but that’s for the future of us all.
Thats the problem. It would be very difficult to get a new instance off the ground unless you were an insider or had inside connections. If you have a cabal of existing admins acting as gate keepers you could keep outsiders from abusing the system easily, but you are also walking right back into the centralized control federation is supposed to prevent.
Welcome back to IRC. :)