I think this is only a religious debate in the US where Trump tied it directly to a certain identity people desperately want to maintain or distance themselves from.
I've never heard it referred to as a religious debate in the US. When I hear about anti-vaxxers complaining, it's from a perceived freedom (not religion) standpoint. Maybe there are exceptions for some religious minorities, but I have yet to hear them.
Agree on the US partisanship, disagree on the religious angle (except to agree that religion could potentially be used, on a small scale (e.g. local churches), to disparage the vaccine).
On another note, I enjoy open debate regardless of the subject, and I appreciate that there are arguments against the vaccine (though I am vaccinated myself).
Not sure if you’re a native English speaker, so commenting explicitly just to help out. “Religious” does not only refer to supernatural beliefs, at least in American English. US partisanship has escalated to a level where it can be easily referred to as “religious.”
Many clearly prioritize it over their official “religion” as you can see with Christians bending over backwards to support Trump even when it puts them in direct opposition to the teachings of Christianity.