Throughout human history, people’s opinions have been based mostly on their own observations and experience. If someone tried to sell a line of BS, a normal person would check the claim against his own experience and, if it didn’t add up, reject the claim. This was known as common sense.
Somehow, that basic reality check seems to have stopped operating. Many millions of Americans apparently believe that their compatriots are dropping like flies from COVID, when their own experience, if consulted, would belie that assertion. But in our world, media hype, the assurances of “experts,” and social media group-think seem to trump lived experience–that is, common sense.