Won't work. With enough resources it's always possible to get secrets out of hardware. Once compromised then every video and photo ever taken by that camera mod

Won't work. With enough resources it's always possible to get secrets out of hardware. Once compromised then every video and photo ever taken by that camera model can no longer be trusted to be authentic on signature alone. Photo/video signing in hardware might actually make things worse by creating a false sense of security. It's better for people to question everything they see rather than trust everything they see.