Just as before, a major part of photo or video evidence in court is not the actual video itself, but a person testifying "on that day I saw this horrible event,

Just as before, a major part of photo or video evidence in court is not the actual video itself, but a person testifying "on that day I saw this horrible event, where these things happened, and here's attached evidence that I filmed which illustrates some details of what I saw." - which would be a valid consideration even without the photo/video, but the added details do obviously help. Courts already wouldn't generally approve random footage without clear provenance.