And there's the problem - some things you have to take on faith or at the very least attempt to mitigate against possible outcomes.
The effects of this virus are quite startling, therefore a sane, sensible person would do everything possible to not contract it.
Putting your faith in numbers when the situation is fluid and unclear is not sensible - taking reasonable precautions against contracting an air borne virus is sensible, whether the numbers add up or not.
A toy example would be that a car moving at speed seems to have a lot of kinetic energy, I'd be better off not using my body to dissipate it, just in case. Whether I have the exact numbers or not, I doubt it'll end well for me.