This could eventually bring us back to a point in the past prior to the invention of video technology. If it becomes impossible to tell if a video was faked, then video will no longer be able to be considered as evidence of anything. It will once again be as if it doesnt exist. We will have to completely discount video evidence, for example in legal proceedings, unless the provenance of such video can be conclusively proven.
We are headed there in a hurry.
In fact, to amend my previous comment, the same will apply to still photography. It will be like we never invented the camera in any form, because we will only be able to rely on other forms of evidence.
Yep. A crayon drawing will be as believable as future video images.