[totony]

I don't think it's quite that. IMO from knowing some anti-vaxx it originates from a rebellion against power more-so than any actual belief in conspiracy. It seems to come from being fed up with being told what to do AND from distrust in authorities (arguably warranted). Conspiracy comes as a post-facto rationalization for some as far as I've seen.

I believe policies like vaccine mandate and the overzealous anti-anti-vax crew are paradoxically aggravating the issue. Making it a partisan issue also seems to force people on the defensive and harden their (potentially unfounded) beliefs, forcing them into the "other camp."

EDIT: My hypothesis on why it comes more from right-wing rather than left-wing people is exactly that right-wing is anti-government power (or more freedom of individuals, usually).