Bizarre, I don’t know what went wrong. Hope this works.
My position is simply this...there is nothing magical about a COVID-19 viral particle that allows it to impart properties to a drop of salt water allowing it to penetrate materials that are known absolutely will stop ANY OTHER PARTICLE of the same size. Masks DO work just based on that.
And the hypoxia effects this doctor touts, although a real effect, happen only to a tiny minority of people, and are easily relieved by simply taking a break without the mask at a safe distance from others and in a well ventilated area and doing some deep-breathing exercises.
If you are really worried about it, get a phone with an O2 sensor (mine has one), or get a finger oximeter (I got mine on Amazon for sixty bucks just to check the phone (and they "do" agree)). I also tried "with" and "without" wearing a mask, and the "hypoxia effect" was about 1%, which was cleared with a couple of deep breaths.
In "civilian" use, I don't see any significant number of people wearing a mask for much more than an hour at a time. Put it on when you before getting out of your car, go shop, return to car and take it off...then use hand sanitizer.
If as much time was spent EDUCATING people on CORRECT mask usage rather than trying to sell the false meme of "masks don't work", we would all be a lot better off.