Exactly this. There is an unbelievable irony in the fact that the current administration is on a intense PR push to get unvaccinated Americans to trust the vaccines and get vaccinated when they specifically communicated during their (Biden and Harris) campaigns last year their distrust regarding the vaccine due to its association with Trump, speed of development, and experimental nature.
This is what happens when people check in their common sense for political allegiances. I have no doubt that if Trump had won, we would still be having this issue of the distrustful unvaccinated, but their politics would be more on the democrats side.