What critical thinking is involved in believing the virus is real? Apart from those who made some independent study I would say there is little critical thinking at all... Just faith in the institution of government and press.
I'm judging that the virus is real and a problem based on having had it, knowing people who died from it, knowing other people who had severe symptoms, from knowing (via other acquaintances) what the hospitals in my area were like, and from seeing freezer trucks full of dead bodies in the streets. OTOH, I'm from an area that got crushed by the virus early.
I can't say for sure that if I were in an area that hadn't had much contact with the virus my "Critical thinking" hat wouldn't be saying, "wait, what if they're just telling us there's a virus outside to keep us locked up".
Until a colleague told me he lost his smell 2 years ago after a serious flu.
I still do believe the virus exists, but not having the equipment to look at it myself how can I be absolutely certain?