No one is censoring anyone. They are free to post whatever toxic shit they want. But we, as an instance, have elected NOT to listen. Censorship would be banning their instance from existing, which IIRC is impossible with federated instances. No, this is just de-platforming. We are turning off the loudspeaker connected to their instance. We don't have to give them a platform. There is no reason to do so. So we defederate.

EDIT: Let me dumb it down further. "We are removing the link to Stormfront from our home page due to their stances." Would you call that censorship? Is it censorship that I would unfriend someone because they are spewing hateful garbage? Of course not. If you really want to read that hate, there are plenty of ways to find it. We just aren't going to help you find it anymore.

Defederation is de-platforming. These hate communities are able to recruit because let them. We give them free reign to whisper hateful falsehoods in the ears of the vulnerable, all in the name of free speech. They can be as hateful as they want on their own, but we are under no requirement to give them a platform to spread their ideologies. De-platforming works, so let the nazis chirp in their own little echo chamber. Keep their hateful rhetoric contained to their own little garden so our vulnerable youth need not be exposed. It's easy to say "just block them yourself," but that doesn't cut off the steady supply of misguided incel-larva to fill their ranks. Drown 'em out. De-platform them. Defederate now. No quarter for hate.