If you want your freedom – whatever that means to you – you go to an instance that represents those values. Admins that run their own instance get to decide how they moderate that instance. And that includes blocking (or defederating) whole instances, communities, or individual users. You don’t have to sign up to one that does something you don’t like.
Besides, you don’t seem to understand the importance of moderation. If it wasn’t for the ability to defederate, we’d have tons of fake instances with fake users creating fake posts. Not to mention people going out of their way to make others feel miserable. Do they have the right to spew their hatred? I have my opinion, but it doesn’t matter. I happen to also have the right to join an instance that has a policy to take care of that stuff so I can browse for things that actually interest me.