Are we talking about believing the vaccines don't work/help?
There are varying levels of skepticism.
Let's say you said, "the experts agree, the vaccines are effective, safe, and everyone who can should get them"
The experts agree - we don't trust those experts, they've been lying to us all through covid. And any expert who disagrees is silenced.
They work - sure, but not as much as claimed.
They're safe - possibly, though we can't know for sure yet, and there are side effects being pushed under the rug.
Everyone should get them - not me, I'm already immune, and if you dare try to force me, there's no way I'm ever doing it.