I think it's worse than that since, as described in the article, NFTs don't include a hash of what the link points to. So you own a certificate that describes the content of a link in the very literal sense of describing the characters in the link URL and not really anything more.

> ok so you own a certificate that describes the content of a link

More precisely you have a certificate that says you own something (often ambiguous, though this could be precise; ambiguity is a choice in the minting of an NFT rather than a fundamental issue with the technology) relating to the content described by means of a link (the NFT may or may not include additional description of the content via metadata.)