@youronlyone because the Fediverse still has an account hooked to a server and an admin can block that. You migrate, you lose your posts, and migration is not seamless across diff networks.
Nostr requires no account creation on any server, and the keypair you use works seemlessly across any clients or Nostr websites. Any post you make with Nostr relays through 8 or more (of over 2,000) relays. Even if one relay owner were to "block" your profile, it still flows out seamlessly through any other.
tallship