IE... somebody could sell the object and keep the NFT, or vice versa. There's no legal concept tying the NFT to ownership of the object, except perhaps indirectly via contract.
It's similar to what's been done in the high-end art world for years. People who buy a $50M painting don't usually hang it on their walls, they just leave it in a vault and get their name recorded on a public art registry saying they own it.
Seems like a similar legal framework granting NFT owners either copyright ownership or a usage license could be interesting.
What happens if someone buys my NFT but I refuse to deliver the physical item? It seems we need to pull in the legacy legal system to enforce the transfer, at which point I wonder what value the blockchain added in the first place.
Blockchains can be useful without totally replacing the legal system. Just making things a little better and more efficient is fine. In this case, it lets people easily trade collectibles without all the hassle of shipping physical items.
Today when you buy a home you have someone go down to the local courthouse and check that there are no leans against the property and no one else is claiming ownership. In the future, you can imagine a world where that title would live on the blockchain and everyone could see the true owner based on their ability to sign a message with their wallet. You could transfer your title just as easily as any other blockchain transaction. While blockchain titles have obvious advantages, they are hard to pull off because you need 100% participation of everyone in the community for it to work.
The reason we're seeing art NFTs take off first, is that you only need the participation of the creator and a small group of collectors. The creator promises to sign all of their work with their digital wallet and as long as the buyer of the NFT trusts the creator, it works.
Isn't it more like "I own an NFT that refers to that thing"? There's nothing to stop the actual owner from 'printing' as many NFTs as they want, right?