> Could Nostr succeed where Namecoin failed? Could Nostr become the layer that will eventually make ICANN and national registers irrelevant?

Probably not.

As of now, Nostr relies on ICANN. Not the protocol itself, strictly speaking, but rather the ecosystem.

Even if we ignore this, however, Nostr doesn't actually address the issue at all.

It's true that one could make a decentralized domain name using Nostr. It's also true that work has already been done regarding this.

However, those domain names are not, and really cannot be, easy to remember. So I don't think Nostr solves this problem.

The good news, however, is that we can still promote .bit domains, or domains which use a similar blockchain-based system. The fact that it's not been successful so far does not mean it cannot be.

Nostr can still be useful to register domains which do not need to be easy to remember or to identify for a final user. The advantage over .bit, .eth or similar domains would be the fact that they could also be free of charge (because the supply of potential domains, all about equally as good, would be infinite).