Signed by who/what, though. There's the rub.
Look at software distribution, today, on the OSs that most people use for the likely outcome.
Yea, I don’t think I buy that we’ll be able to get our act together enough to start cryptographically signing things for reasonable authenticity. My hot take is this actually drives people back to mainstream media as arbiters of truth.
Maybe by the people in the content themselves
Signed by the President of the United States for example!