Federation is critical to the development of alternative social networks. The reason people use specific social networks is because other people are on them. If there’s an open source social network app that isn’t federated, then everyone using sites powered by that app is isolated. With federation, all instances of the social network can interact with each other. Different instances can pop in and out of existence and the ones that stick around can become popular.
It’s better for new social networks to be federated then isolated.
You can always install your own instance of the site and have whatever rules you want for it, just be warned that uncensored alternative social network sites tend to attract white supremacists and the like.
I’m in a hard place as far as deciding how I want to moderate my site because it’s going to lean right most likely. If you make the instance openly left wing then it might not be an issue.