Will it ever work until a TPM like module is directly integrated into camera sensor? Older attempts of Nikon and Canon got broken, same had happened with C2PA implementation for Android - if it gets anywhere close to CPU it is insecure.
Security is never a binary property, however, and can usually be better expressed in terms of how expensive it would be to subvert a given mechanism. "This image is either authentic or would have cost at least $x to fake" is already much more useful than nothing at all even without $x trending to infinity.