What you're literally buying is just a uint256 number + the address of the minting wallet, not even a URL or link. The URL comes from feeding that number into a function of the smart contract, but you don't "own" that smart contract. You just "own" the number.

See the spec as it were: https://eips.ethereum.org/EIPS/eip-721

> The pair (contract address, uint256 tokenId) will then be a globally unique and fully-qualified identifier for a specific asset on an Ethereum chain.

And while the code of that smart contract is immutable, it's still code and the outputs of any given function can change even when given the same inputs. The code can of course poison itself by observing other state or even delegating to other contracts, allowing forms of mutability of the contract itself.

Which, reminder, you don't own in an NFT. So hope you really really like the uint256 you bought. Also hope you have a good grasp of solidarity & really did an analysis of that smart contract first. That's a totally reasonable thing to expect people to do, right?

The content hash would prove nothing. What you're buying is "this NFT was minted by this artist, as confirmed by their Twitter or verified OpenSea account or whatever". The value is totally dependent on the social contract. Some random person minting the same NFT with the same hash would be worthless, unless they impersonate the artist.

Fair point. Indeed content hash and signature from the artist would have to be on-chain, and somehow the signing party needs to be established as the real one as well. So... it's even worse that none of that is happening. With NFTs, to me it really just looks like BS all the way down.

I also think it's BS but not because of what the NFT contains or not. The signature is already intrinsically part of the NFT since you can see what wallet minted it on the blockchain. When you mint an NFT you sign the transaction on the blockchain with your wallet.

As you say what actually matters is proof that the signing party is the real one. And this is where the social contract matters. What gives it value is that artist X says they own wallet Y and that you can see that NFT Z was minted by wallet Y. It's just a fugazi but it can't be fixed by adding stuff to the NFT object.