I guess a lot of people (extrapolating somewhat from myself) feel like wearing a mask when you go in a building other than your home is not extreme nor has it b

I guess a lot of people (extrapolating somewhat from myself) feel like wearing a mask when you go in a building other than your home is not extreme nor has it been enforced in an extreme way, contrasting with your hypotheticals. From what I read on the internet, it's long been a custom in many places in the far east to wear a mask whenever one has or might have the cold or flu or whatever. At this point, I'm thinking why shouldn't we westerners adopt that, going forward? It appears that wearing masks drastically reduced flu transmission, which seems logical given that it's much less contagious than covid-19. That presumably saved many lives. And the common cold is not worth developing an advanced vaccine against, but what would we be losing if we prevent its transmission? So I don't see why masks are a bad thing even if covid vanished tomorrow. There are so many measures we take to mitigate things that have substantial known and unknown risks, so it's mysterious to me why people are so vehemently against one with no downsides.