Earlier quoted context omitted.
DNS is centrally controlled by ICANN. There are alternatives like ENS. I don't mind Nostr just simply having its own system.
DNS is both. There are the universally accepted root servers, ICANN, national registrars, etc. But nothing prevents you from trusting additional root servers, with TLDs if your choice, delegation of subdomains from them, etc. All the standard mechanisms will just work. Your router likely supports the .lan TLD out if the box.
DNS the system that we all depend on depends on the assumption that we all use the ICANN root servers.