Most people are bad at memorizing npubs or IP addresses. Therefore most people tend to depend on naming systems like DNS.

Yeah, with IPv6 you can have thousands or millions of addresses, just for you. You can have a public IP for every service, for every tweet, or whatever. So IANA cannot hide behind the narrative of the scarcity of IP addresses, as they do right now. And ISP's don't even give you a public IP anymore, you just get a NATted address in many countries. That's one of the reasons why DHT's don't work in internet scale, because holepunching is a pain in the ass. Even if they give you a public dynamic IP, you can't use it to run a service without a dyndns because it's dynamic. And peer to peer stuff depends on being able to reliably find each other.