Ethereum is an unpermissioned network. Anyone is free to join or leave at anytime.
>how are you preventing me from saying "I'm part of the .crypto registry, totes.")
The registry would be a smart contract. There doesn't fundamentally need to be an owner.
>how are you preventing me from saying "I'm part of the .crypto registry, totes.")
Name resolving doesn't have to be done by ICANN's domain name system. You can have alternates that do not depend on centralized servers.