Are you saying that KN95's are not worth wearing?
I'd need to go searching for articles/studies I've seen that say otherwise, but I'm pretty confident that they're out there.
N95s are certainly better, but only if you can manage to keep them on for the full duration of possible exposure - no nose scratching, no sips of water, no snacks...
Is that feasible on let's say a coast to coast flight?
@joeinwynnewood @GreySkies @augieray Against R₀ ≅ measles current circulating variants, you want a continuous, well-fitting, elastomeric gasket against bare skin. (Block the filters and inhale and the mask crumples but does not leak as you hold the inhale.)
COVID has evolved; what was more than sufficient against the wild type is not necessarily sufficient today.
COVID brain damage mechanisms that are inescapable and permanent are now known in detail. I'd stay off the flight.