[smt88]

> Plus you can add a secret to the paper that allows unlocking the content at the URL, which normal users would not have. That secret can only be decrypted by the owner of the paper.

You cannot do this with an NFT unless the server that the NFT is hosted on supports it (and has awareness of the blockchain). Then it becomes centralized to that server. You couldn't do it with IPFS.

[yayr]

you're right. Thanks for pointing that out. The encryption of the secret has to happen of chain, so that the secret is still secure. So typically that would be done by the provider of the NFT and thus is not decentralised. Essentially, this would eliminate the need to put the secret on the chain at all. Only the proof of ownership would be on chain.