Dear @theprophet,
You are making a common error in your assumptions.
A mask won’t work to protect you if someone with COVID sneezes on you, that is right. But it protects others from your own sneezing COVID saliva by not allowing you to spread it.
Since we don’t know for sure who has COVID and who doesn’t, everyone should wear masks as a measure of Bein Adam LaChaveiro to make sure we don’t C”V accidentally make our friends ill.