> It was primarily well-educated upper-class white liberal "granolas"

I don't think those people stopped being antivax, if anything they feel vindicated.

You should consider thinking of people as precious, rather than these odd fine tuned segregated negative groups seemingly based on skin color, political leanings or social status.

By the numbers, the upper-class white people were a very small fraction of the anti-vaxxers in the US. The majority were (and still are) Mennonites, Amish, and ultra-conservative Jewish communities.