>A regular mask is good at “curbing the fanout” so to speak, but not so great at filtering incoming air.
That applies for cloth masks and alike. N95/PFF2 is a protective gear and should filter ~95% of particles where N99/PFF3 is ~99% if given a perfect fit. Beards and other stuff can reduce the efficiency to ~30% though.
> Meanwhile, masks are not free.
But they are not expensive and can be rotated.
> A properly worn mask necessarily obstructs breathing.
Only if you already have difficulty breathing. Studies show no impact on blood oxygenation whatsoever due to the usage of masks in normal situations. What they cause is discomfort due to retention of breath humidity and heat. It sucks to wear a PFF3 while doing intensive exercise,
> One risks becoming infected by their own mask which accumulates virions in circulation.
Any viruses that accumulate on a mask you would be breathing otherwise.
> ...reduced exposure to viruses long-term may weaken the immune system—though.
That makes sense. The nose epithelial cells are the 1st line of defense against airborne pathogens. By reducing our exposure we are reducing the efficiency of those cells.
> Now consider real life, where not everyone wears masks, and my guess is depending on where you are easily less than 10% of mask-wearers wear masks properly. They don’t wear masks over their nose, leave huge gaps between the mask and their face, take off their mask to sneeze or cough (I kid you not). They try to make it easier to breathe, and by extension defeat the point of wearing a mask.
True. Where I live masks are not enforced, we are in the summer and >90% of those I see are not using it. But the few that are still using it are doing it properly.
> Nevertheless, a measure has been taken, and local policymakers may now rest with a false sense of security.
I agree with you but not because I don't think masks work. It's just that people think that now that they have took the jab and put the mask they can do whatever they want including staying for hours in a fully occupied and closed room where a guy is coughing non-stop. It's just that people are stupid and irresponsible.
When I studied workplace safety and health we learned that protective gear is the last measure you adopt. If you have place where exists a risk of people falling you first should attempt to eliminate the risk and improve the ergonomics of the place, like installing guardrails. If that isn't possible you enact administrative policies like forbidding from transiting in the dangerous place unless they have authorization and a reason to be there. And only then you provide protective gear for those.