Please read up and educate yourself on why masks are being requested to be worn in this case.
Hint: It's not to protect yourself from other people, it's to protect other people from you and what you might be carrying.
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While true, that's not the reason you should be wearing a mask.
The masks being advocated for people to wear aren't filters to keep things out, they're just cloth to keep the particulates you give off from getting OUT.
The rest of what you're saying is true though, because if everyone wore one, the risk of transmission goes way down.