“If some person you dislike got robbed in front of your house, you could be compelled to help them by supplying your video footage even if you don't want to.”
No, I'm saying that if I really owned the video, I could decide whether or not the police can use it. I'm not arguing whether or not the police should be able to have access to private video, but that you don't really own the video if you can't tell them "no" when they subpoena it.
You say that like it’s a bad thing…