The thing your missing is ICANN is headquartered in the US. The US political situation is dire and I think this could be a real danger for the internet at large. We might end up with disagreeing DNS worldwide at some point. E.g. if you hold a domain and have a non-authorized viewpoint so your DNS entry gets snuffed.

But from a practical point of view a decentralised system should not rely on domain name ownership. Any computer can generate a private/public key pair, which is all you need for identify.