Yes, fiddling with other's videos is dishonest. Should be illegal, if not. On the not live live my first thought, years ago, was maybe many were live when posted and the live just stayed there. Maybe because of our time difference i got caught by the fake live more than if i was in the States so was more aware of that than might have been. Obviously there would be the intentional scammers too.
If one is outside of respected sites accepting videos as true now is as risky as taking photos as true. So one could ask why bother going there.