For some sorts of recordings, this seems like the sort of thing that a blockchain should excel at. My camera could submit a proof of work with the cryptographic signature of a recording embedded in it. Presumably, it's expensive to run a GAN or whatever other algorithm to generate a good fake video. So, if the signature was adopted into the blockchain sooner with respect to the timestamp of the recording than how long it would have taken to fake it, future viewers of the video could confirm that the timeline fits.
Of course, this depends on a large-scale discrepancy in those timings. And it's only really useful in cases where the timestamp of the video can be separately established in some manner, such as a publicly-verifiable schedule.