[esclerofilo]

I believe that's not what they're saying. It's signing hardware, like a camera that signs every picture you take, so not even you can tamper with it without invalidating that signature. Naively, then, a signed picture would be proof that it was a real picture taken of a real thing. What GP is saying is that people would inevitably get the keys from the cameras, and then the whole thing would be pointless.

[cwkoss]

Yep.

A chain of trust is one way to solve this problem. Chains of trust aren't perfect, but they can work.

But if you're going to build a chain of trust that relies on humans to certify they used a non-tampered-with crypto camera, why not just let them use plain ol cameras. Adding cryptosigning hardware just adds a false sense of security that grifter salespeople will lie and say is 'impossible to break', and non-technical decision makers wont understand the threat model.