In the past all respiratory viruses were symptomatic before the infected person could spread them. The infected person has a fever, congestion, cough or other symptoms. So it was easy to isolate the infected and break the chain of transmission. There are many ways to do this. And it's why in some places, like healthcare setting you are asked those questions and your temperature it taken before you're allowed to enter.

But with SARS-CoV2 it is more infectious before the infected have any symptoms. So there is no way to isolate people that have it before they can infect others.

So when Fauci wrote that email it was still assumed we'd be able to isolate those with symptoms and control outbreaks. However it was confirmed about 30 days after that email was written that SARS-CoV2 spreads asymptomatically. And later it was confirmed that it was less infectious after symptoms appeared. And then it was confirmed that it was actually the immune system response following infection that was what was really effecting people.

So at that point it became important for everyone to wear even simple masks. Because they greatly reduced the asymptomatic spread of SARS-CoV2. Because they stopped the infected person from giving it to someone else. But yeah, freedumbs and all of that.

But yeah, I get that people not capable of thinking for themselves would find that hard to understand. They just follow along whatever some authority figure in their lives tells them and claim they are thinking for themselves.