I recall articles saying that there's no point in lay folk wearing an mask. They're impossible to wear properly without four years of medical training, presumably mostly focused on mask wearing rather than silly things like anatomy, so anyone else wearing one is a complete waste. Leave it to the professionals.

I'm exaggerating but not by much...

Contrast with the current messaging. They work but are in short supply. If you have a stash of new surgical or N-95 masks, please donate it. If you have a used mask, please continue wearing it. You're encouraged to make, wear, and sell/give to anyone non-medical-grade reusable masks. Anything is better than nothing.