The article makes some vague reference to problems which forced health organizations to abandon KN95s, but this is the first I'm hearing of it and there's not enough information to look up what they're talking about.
I had an air purifier running indoors which kept my indoor air to around the equivalent of AQI 10 or better most of the time. (I say equivalent because my particulate matter sensor gives ug/m^3 and counts/cm^3, not AQI, so I had to estimate AQI).
If I took the mask off outside, the difference between outside AQI 200+ and indoor AQI 10 was immediately apparent.
For everyone who is not in some job with a high risk of prolonged COVID exposure, I'd recommend going ahead and getting a KN95 even if it uses ear loops and so won't be as protective as an N95. It will still be a lot better than surgical-style masks or most homemade masks.
Use the cheaper surgical-style masks if most other people around you are also wearing masks. That's the case here for 99% of the people I see in the grocery store. But I'm not confident that people will keep that up for as long as the science says we need to--we Americans have a habit of ending things too soon. If mask wearing falls off before it should, I've got my box of KN95s to switch to.
There doesn't seem to be any shortage of KN95 masks. There are dozens of boxes of them at my local Lowe's.
So, why is the nurse in this story wearing an N95 for weeks, instead of wearing the plentiful KN95 mask?
Am I missing something?