>he was constantly on social media

That's how.

It's not like you log in one day and instantly believe all those things. It's a slow and incremental brainwashing process that's exacerbated by social media algorithms designed to suggest content similar to what you're already viewing to stop you from going outside.

And there is a brand new bunch of people who were new to all this and only started watching covid conspiracies on YouTube and Facebook who are well on their way to harassing mass shooting survivors in oh...well anytime now actually.