I personally know medical people and one epidemiologist - they disagree that masks protect you from any virus...the best they can do is limit the spray of those who are sick...it’s why surgical crews wear masks - to prevent them from spreading germs to a vulnerable patient, why they wear masks during high outbreaks - in case one of them is sick w/o realizing it so it doesn’t spread throughout the staff.
A healthy person benefits almost zero for a mask - a lot of those countries you speak of have a high incidence of mask wearing due to pollution in the air...
Americans do not seem to have the IQ to understand how masks work. They are not to protect you from being infected they are to prevent you from infecting others. If everyone wears masks it reduces transmission rates by 80% or more. I am shocked at this point any medical person who would say not to wear a mask and doubt they told you what you are saying.
This is why the U.S. is going to end up having the highest infection and death rates.