Earlier quoted context omitted.
The author could use a unique private key for each blockchain NFT if they wanted to avoid that.
The problem of how to associate a NFT with a physical object is a different one from the transfer/spending problem. I think that is the "minting" problem. An artist simply signing stuff does not even prove that a physical object corresponding to the token exists. I like to think of other use cases, like real estate or stock options. If you talk about a plot of land, it seems feasible to find a unique identifier (you…
A deed digitally signed by the government's private key satisfies this need without a blockchain.