So face masks for the average punter are worthless at best, more harmful at worst
(I've gone for the 'putting words in your mouth' angle )
I don't know - but I would have more faith in keeping my distance than a damp patch of snot.
If I am in a confined space then, in the current mood, and people are genuinely scared, I tend to wear a keffiyeh 'coz it looks cool, probably better for other people in that there's not jets of instant death flying out the sides if I exhale, can be laundered, and handy if I decide to go on jihad.
Mostly though 'coz it looks cool.