I think part of the problem is that the science keeps changing as we find out more. Were masks going to help with Covid? No, then yes, then kind of drifting back toward maybe no.

Are RNA vaccines going to work without having many side effects? From what we know now, yes. We may learn something from trying it large-scale, though. (Just today there was this article on HN about men suffering unexpected levels of heart complications.)

This leads to people who are "pro science" but have out-dated science. And many people, even those who want to "follow the science", have run out of time and energy to keep following the science. So they treat "science" as frozen in time, not as a process.

And then you have people with vested interests and/or political angles. That includes the vaccine makers, and at times may include the CDC.

All in all, sorting out the science has become a real bear on this particular issue. People get tired, and freeze at the position the science supported when they gave up tracking.