You're missing the point. Facebook / Twitter / etc verify the crypto signatures on media ingress. Then they can give proper attribution and show a checkmark or

You're missing the point. Facebook / Twitter / etc verify the crypto signatures on media ingress. Then they can give proper attribution and show a checkmark or something that attests the media hasn't been altered. So in your feed, there will be some media with checkmarks and some without and you can choose which to believe more. Alternatively, a competitor could come along and reject all media that doesn't pass cryptographic verification.