I know you want to believe that as it is the narrative and most anti-vax people getting media time are in the pro-Trump crowd, but before COVID hit in my part of the country, anti-vax was more of a left-leaning sentiment. The most anti-vax areas of California were deep blue granola eating areas. The most prominent face for the anti-vax movement was Jenny McCarthy who is very much not a Republican. She even quit the View when they asked her to pretend to be a Republican for ratings. Neither side of the political divide is free from nutjobs, and neither side should be characterized by their most extreme supporters.