I think the disagreement about masks between much of public and health professionals is because of a lack of precision about exactly what they are talking about - there are many different types of masks, and the skill with which they are worn seems to vary highly in the US
The statements that masks offer protection to the public may or may not be true depending on precisely what masks are being discussed, and how carefully they are donned, worn and removed, and in what environment they are worn.
Almost no masks, except N95 respirators, really offer true protection to the wearer in a highly contaminated virion infused environment - If they do protect the wearer, then the outer surface of the mask is highly contaminated, and needs to be removed and disposed of carefully with sterile technique. Most health professionals all know this and do it well, but they also see the public make many many mistakes with masks, and those mistakes MAY NOT be risk free, to the wearer, or the public. This causes some health professionals to be less than enthusiastic about the public wearing masks. Risks versus benefits and all that. Mask wearing poorly done might lead to a lethal outcome for someone. Oh my!!
However, there is overwhelming evidence from much of Asia, that most masks do help protect the public from infection in a general public environment, not in an Emergency Room. Probably because if masks are worn by unaware infected people, their spittle does not fly 6-12 feet into the local environmental air, but is captured by the mask they wear, and thus helps protect their fellow citizens from that exposure. If those non-infected citizens are also wearing a mask that removes 50-70% of airborne particles, their risk is also even lower still. It has even been suggested that the folks who get Covid while wearing a mask, aren't as sick because the toxic dose was smaller than if they had not been wearing a mask.
Wearing masks does not diminish the importance of social distancing, it is additive to social distancing.
As to comments about used masks blowing down the gutter, this is another point that demonstrates how careless many people are about proper mask techniques. I see so many folks wearing them below their noses, and that is obviously a waste of their time - it protects neither the wearer nor their fellow citizens.
Last summer there was an thread here on Cake about disinfecting mail and packages from Amazon - there can be no doubt that both of these items are potential sources of viral spread - BUT - the reality seems to be that if one is reasonably careful and washes their hands after handling mail and packages and groceries, the risk to oneself is pretty low.
One MIGHT suggest that many Americans are really not very concerned about the health of the elderly citizens around them - for the elderly, over 80, are really the people at the highest risks of dying from Covid 19.
I do wear a mask when I go out into stores, not because I really believe the paper surgical mask I bought from China, via Amazon, will prevent me from getting infected if I am in a crowded, indoor, poorly ventilated space, but might help to protect my fellow Americans if I were to become infected but unaware, so that they can feel safer.
My primary protection is staying out of doors, over 6 feet away, and frequent hand washing. So far, it seems to be working.
And then we have politicians who refuse to don masks. Just imagine if the virus we are dealing with were Ebola, and about 90% lethal, and not SARS Cov 2.
Do you think those politicians would allow people around them with out masks??
Res ipsa loquitur!!