Well, it's a bit more complicated. The surgical masks don't create a seal; so if someone sneezes on you and you're within that 6 feet distance, the virus will easily get access from the sides; theoretically (N95 is different). Hence the distance is recommended, and yes, mask is an added barrier, not the best, but something is better than nothing.
As for Asian countries, more than the masks, they were successful in the social distancing, quarantine and shelter at home measures. I think those did more than the masks tbh.
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