You are in Australia, where governments are being sensible. So that is a no go. Now, if you were in one of the US states that are being stupid . . . . .
You didn't say that, you said: "You know how you go from 3 to 10,000 cases? By not wearing masks."
So your assertion was that regardless of what government does, if we do not wear masks we'll go from 3 to 10,000 cases. Which is abject nonsense. Almost as much nonsense as our government, which has -
- closed retail which is out in the open with constant fresh air, while keeping open retail inside shopping centres with recycled air, as you can read
here, and
- insisted that we face having a healthcare system overwhelmed and so need to lock everyone down again, while at the same time keeping medical centres closed and cancelling contracts for ICU gear, which you can read about
here.
Our country does not face the same problems as yours. This is partly because of the irresolute inadequacies of your government, but also because of your culture. Your country has twice the lethal car accident rate, and workplace deaths rate, and many multiples the accidental firearms deaths rate. America is quite simply a more careless culture than comparable Western countries.
Here people who have tested positive or who are awaiting tests mostly isolate themselves. I would expect fewer to do so in the US, not only from carelessness but also from necessity, as they lack a social safety net, so those minimum wage workers in customer service roles have to go to work, or be evicted or not eat.
In America, I would wear a mask, and probably a kevlar vest, too. Here I don't have to.
Culture matters. Australian culture has the flaw of an instinctive turn to authoritarianism. It comes from our convict heritage, the government can't help but think of themselves as prison wardens. American culture is careless and fails to look after its most vulnerable. Here the greatest danger to our health is the government, in your country it's your fellow citizens being idiots.