Well... I'm not gonna go through 20k posts to try and find it again, but there was an article linked to somewhere here on FR several days ago about how China was
still short on N95 masks for themselves, mainly because the media is hard to make, and the machines to make the media are on very long backorders, and too expensive for a lot of the smaller Chinese companies to afford. (The production machines are even harder to make properly, as well.)
We see these vids of "everybody" in China walking around with masks, but, lets say actual demand averages two masks a day for 1/2 the population. That'd be 1.4 BILLION masks a day - a pretty tall order for even China, just to keep the virus from restarting in a big way.