Nothing improper with people disagreeing.
I'm not only a lawyer, I'm also a physician (a DO).
I never practiced medicine, other than to complete my internship.
I am licensed in three states, should I ever choose to hang my DO shingle.
There is no scientific evidence that suggests wearing a mask protects the wearer, other than minimally.
As far as protecting yourself, the best approach is to distance yourself from others (I try to stay at least 10 feet away), don't touch others, and avoid crowds.
A mask is worn by surgeons (and the operating room team) to prevent infecting the patient during surgery.
No ethical surgeon would operate on a patient if she were infected with a communicable diseases, even if she wore a mask and protective garb.
If you wish to take precautions, buy a gas mask or respirator.
I wore a gas mask yesterday on our outing to a nearby Walmart.
A piece of unsanitized cloth or paper over your nose, mouth, and chin does very little (if anything) to keep you from ingesting germs.
A mask does nothing to protect your eyes or ear canals.
To add additional layers of protection you might wish to consider ear plugs, ear muffs, and goggles to protect your eyes.
A mask will not protect you if your skin has cuts, abrasions, or sores.
The main reason for the mask is to protect others, much like your surgeons example above. If they're not effective at protecting others, then why would surgeons bother?