Lots of ways to sign photos and videos today that should make them fully verifiable in the future (assuming public/private key cryptography remains secure). For stuff that isn't signed, it's not like good old detective work can't verify in a lot of cases. Phone records, eye witnesses, additional unpublished recordings, etc.

Also being verified really only matters when it comes to "truth" as defined by law. It's not like your family won't enjoy your videos of Christmas '23.