>which wasn't true before the pandemic

if you mean to say Japanese collective mask usage, let's say seasonally, even if not ill, is no different than western nations.

Yes they wear when sick, but also as preventative measure, on public transportation, around crowds etc. Not like shoes (all the time), no.

US has never worn masks, even during flu season, (though I did read it caught on during Spanish Flu but even then it was socially pressured against, for some reason).

Here's another [0] from 2015: "Let's talk about Japan and sickness masks" which talks about Japan's mask culture going back to 1918, and that people wear them at particular times of year as prevention, in addition to when sick.

[0] https://kotaku.com/lets-talk-about-japan-and-sickness-masks-...

My original "practiced widely" was meant to imply broad acceptance of it, when necessary, not that it was practiced constantly.