Yeah true, that’s a fascinating challenge that I haven’t seen particularly well discussed anywhere in detail.

It needs to be really well protected so that the owner, and only the owner can disable the chain of security, but that they can do it without unreasonable overhead and without actually involving the manufacturer (in my opinion. To handle examples like manufacturer trying to lock-in or charge fees or simply going out of business)

Perhaps the owner mints a public key pair, and the device only unlocks with proof of the private key. But in a way in which is easy for your every day person.