I‘ve been in China from the very beginning of the Pandemic, and possibly will continue for at least one year. And for some very "prepper" accident, I personally purchased a 3M HF-52, in Dec. 2019, right before the lockdown took place.
And with quite a reasonable check frequency of the availability of the mask & replaceable filter, I can personally confirm that (at least industrial) filters have NEVER been out of stock even during Jan./Feb. 2020. A simple fact is that despite the public can retrieve knowledge from the internet that it's almost equivalent, few choose to purchase it.
In an Asian country like China where physical appearance matters most when going out to adolescents, the feeling of "standing out" might be a disaster.
When discussing it in the rationalist community, we would seldom discuss whether appearance matters in front of life risk, but this might still stand for the general public.