As the article points out, many NFTs are implemented by storing a URL in the blockchain; the digital artwork sits on some server and is reachable by that link. Fine, you can prove that you own the URL. But what that URL points to can change out from under you, so there's no way to make that trustless. If you own the domain and the server that it points to, the registrar can take the domain away from you and give it to someone else.
In a sense, NFTs are a lot like those schemes we used to see where some company will promise to name a star after you, even though no one recognizes their authority to do this. Fine, that URL is "yours". You just own a sequence of bytes, the ones in the URL, not the ones that the URL (temporarily) points to.
In a sense, NFTs are a lot like those schemes we used to see where some company will promise to name a star after you, even though no one recognizes their authority to do this. Fine, that URL is "yours". You just own a sequence of bytes, the ones in the URL, not the ones that the URL (temporarily) points to.