The reason why people grasp federation easily when it comes to email and phones, but not at all when it comes to fedi is simple:
If you use Gmail or whatever other email provider, you don't become part of the "Gmail community". Communities form at a higher level detached from provider boundaries, and do so just fine. Getting banned from a community has no impact on your email. You choose a provider and have access to all the same communities.
Here, it's all an annoying clusterfuck that requires knowledge about the dynamics on the fediverse before you've even been part of it.