As a physician, I had a hard time understanding the ferocity with which some of my colleagues defended the "science" of masking when the Cochrane review(s) -- largely held to be the pinnacle of evidence-based-medicine -- were so underwhelming. I never had a problem with people arguing for them based on face validity (hehe), personal preference, that they "might" help, were "better than nothing," or any number of softer reasons.
Don't get me wrong -- as a physician I wore an N95 every shift, because I believe that the odds that they might help were much greater than the odds that they might harm. (And because my hospital's N95s are much more comfortable for me than our surgical masks, and other trivial reasons.)
But I had a hard time finding other physicians who were both steadfastly convinced of the incredible benefits of masking and also had taken any time to try to find or read the available literature on the topic.
https://www.cochrane.org/news/featured-review-physical-inter...
> Medical or surgical masks > > Seven studies took place in the community, and two studies in healthcare workers. Compared with wearing no mask, wearing a mask may make little to no difference in how many people caught a flu-like illness (9 studies; 3507 people); and probably makes no difference in how many people have flu confirmed by a laboratory test (6 studies; 3005 people). Unwanted effects were rarely reported, but included discomfort. > > N95/P2 respirators > > Four studies were in healthcare workers, and one small study was in the community. Compared with wearing medical or surgical masks, wearing N95/P2 respirators probably makes little to no difference in how many people have confirmed flu (5 studies; 8407 people); and may make little to no difference in how many people catch a flu-like illness (5 studies; 8407 people) or respiratory illness (3 studies; 7799 people). Unwanted effects were not well reported; discomfort was mentioned.