I think the anti-vax thing is borne of a distrust in mainstream culture taken way too far.

You’ve got the hippy dippy vegan raw food fixie bike Macbook Air crystal healing hibbity jibbity crowd. As prone to woo thinking as they are, they can raise a legitimate point that the medical and pharmaceutical industries contain no small amount of bullshit that needs to be addressed, they tend to take it to an extreme and swear off science as a whole.

Then you’ve got the truck nuts gun fuck church of Fox News racist asshole crowd. These folks tend to not be well traveled or well read, they’re not exposed to a lot of ideas, they have their in group, which means people who look like, talk like, sound like, and hate like them, or there’s exile. Appearances are everything. You have to be seen hating what the group hates. What does the group hate? Whatever it is that The Other wants. In this case, The Other are Democrats. Democrats want people to take vaccines, they have to thoroughly hate vaccines. Democrats want clean energy? They have to be seen breaking solar panels and spewing black smoke from their gigantic trucks. It’s all performative hatred.