Masking & social distancing were what ended the "Spanish flu" of 1918. In San Francisco, people who refused to mask faced such punishments as fines, prison sentences and getting their names printed in the paper.

The rich, including San Francisco's mayor, were occasionally caught without masks but never went to jail.

It's a bit aggravating that there's always been a really unfair class angle to these things, like when elites got the first covid vaxes.