There’s a psychological phenomenon called “solution aversion” that explains a lot of… fairly dumb responses to real problems.
Basically, if you don’t like a proposed solution for a problem, it’s a lot easier and simpler to deny that the problem is really a problem than it is to take issue with the solution.
You can see this with Global Warming. The costs of fixing it are large, the solutions are challenging to implement, and will likely have lots of costs for lots of people. But what if the earth wasn’t really warming? So easy, then! Then we can just ignore it.
One problem with this is that once you’ve decided something isn’t a problem, the aversion continues even when the solutions change.
When there were really no good solutions to Covid aside from massive societal restrictions on movement/activities/etc., the solution was very costly. So a lot of people decided that life would be better if Covid wasn’t really a problem. Now that the solution is actually pretty easy and cheap, well, sorry. I already decided it wasn’t a problem.