I’m fairly certain that the source for this is bank robbers of yore. But this goes under “we do this, because we’ve always done it that way”, and it’s the absolute worst reason to keep doing something. I, for one, enjoyed and supported my right to wear masks for the sole reason that it hid a good part of my face. Didn’t do much for facial recog, as we saw, but humans have a hard time identifying and remembering faces without seeing a mouth. I knew the masks weren’t real respirators and weren’t nearly as effective as they could have been (the reason I wore an actual respirator pre COVID and during), but I very much enjoyed the added privacy for everyone nonetheless.