It would be nice if none of this was necessary... but we don't live in that world. There is a lot of straight up bullshit in the news these days especially when it comes to controversial topics (like the war in Gaza, or Covid).
You could go a really long way by just giving all photographers the ability to sign their own work. If you know who took the photo, then you can make good decisions about wether to trust them or not.
Random account on a social network shares a video of a presidential candidate giving a speech? Yeah maybe don't trust that. Look for someone else who's covered the same speech instead, obviously any real speech is going to be covered by every major news network.
That doesn't stop a ordinary people from sharing presidential speeches on social networks. But it would make it much easier to identify fake content.