And private information will probably one day no longer exist. Imagine some kind of device that can scan the neurons in your brain along with the electrical/chemical state and somehow extract information from that (such as a memorized cryptographic private key). Let's just throw our hands up and give up on cryptography altogether.
Even a pharmacological approach is a side channel attack which no one seems to care to distinguish between attacks on or flaws with the underlying idea. When discussing the merits of blockchain technology we are allowed to take for granted its very obvious underlying assumptions. Namely that there exists private information held by a user of the system.
That’s not true.
I mean, even if the access to the NFT relies solely on material in your head, there are pharmacological approaches, among others, that while not necessary reliable, can cause you to give up information without meaningfully willing it.