The Hacker Ethos is to build your own media platform and stop whining about someone else’s (unless net neutrality is at play).
I think this is actually why the Twitter approach ("some or all of this tweet is disputed") is a good way to go. You're providing more information—links to people who disagree—rather than hiding information.
All of that said, I recognize that disinformation and misinformation is a serious and tricky problem. I think the American right partially has themselves to blame for throwing so much mud at the wall. I understand YouTube not wanting to be hijacked and used as a political vehicle. But at the end of the day they function as a commons, and I think society is worse off when they censor content like this.