All of it is driven by the for profit healthcare industry, in the end.
Why do MAGA chucklefucks not trust the healthcare industry and think vaccines are poison? Because they're aware of the reality of the healthcare industry mostly existing to turn a profit, and not existing to help patients. Honestly, most MAGA chucklefucks are upset about the same shit we are but they lack the education to know and understand the sources of their troubles, and instead resort to idiocy like racism. They're smart enough to pinpoint the medical/pharmaceutical industry as a problem, but they're not smart enough to figure out that it is specifically the US's way of doing it that makes it so hard on them and that the pharmaceutical companies may be selfish and greedy, but they tend to not be completely outright evil and looking to kill people (dead people can't pay recurring medical bills). Worse, they're also not smart enough to understand (or not compassionate enough to care, maybe?) how their rejection of vaccines hurts other people in the process.
On top of that is the very real issue that COVID vaccines are no longer paid for by the US government, have inconsistent coverage on where you can get it (my partner was turned away at CVS because her insurance wasn't accepted there, mine was. She had to wait two more weeks to get a jab elsewhere), and for the uninsured, it's completely cost-prohibitive. It's over $200 which is not an amount of money most US citizens have laying around every six months for a current COVID booster on a disease that isn't going away.
The corporate and political class are literally bleeding the workers of the US dry and making them unhealthy, long-term, and they don't care as long as their profits in the short-term are "good enough."
EDIT: Describing behavior is not excusing behavior. There's a reason I included the "or not compassionate enough to care" because god damn, that's a lot of them.