I was raised in rural Missouri in the 70s. Parents were so supportive of vaccines then, we actually received the shots at school. I was in the generation at the tail end of smallpox vaccination. One of the differences between then and today, other than people's unfortunate propensity nowadays to accept conspiracy theories as "proof," is there were family elders still living who had memories of the horror of unchecked smallpox.
If there is a mass measles outbreak, it's going to be so much worse than these idiots are apparently capable of imagining.