I may misunderstand how the fediverse and the software works but my understanding is content such as images gets copied over to federated servers and so it seems to me like the ability to defederate would be a requirement in order for servers to stay in compliance with the law and be able to limit various illegal and morally horrible materials from being copied onto their server and network.

Given that (unless I'm wrong about how this works or there's another way around it I'm not thinking of), at the end of the day is it really possible to not have the ability to defederate? There will be times when it would be needed it seems to me. Or for malicious bot servers, nazis, etc. — lots of potential reasons a full defederation would be desired or required.