The first consequence of this tech is that we'll have to stop trusting video evidence. What you describe is a use case that will only be valid for a short period of time while society adjust.

What GP is describing is the long term consequence of not being able to trust video evidence. Now even if you film someone red handed, they can deny it.

Another dire consequence is that the entire archive of all videos filmed since the beginning are now tainted by doubt. Any past politician speech, any past horror caught on film, etc. can now be said to have been crafted recently.