Edit the metadata in what way? It's a cryptographic hash.

If the bits that make up the video as was recorded by the camera don't match the hash anymore, then you know it was modified. That doesn't mean it's fake, it just means use skepticism when viewing. On the other hand the ones that have not been modified and still match can be trusted.

Essentially 0% of professional photography or videography uses "straight out of the camera" (SOOC) JPEGs or video. It's always raw photos or "log" video, then edited to look like what the photographer actually saw. The signal would be so noisy as to be useless.