As I understand it, Japan is seen to be like a parallel universe where the American South successfully seceded but became technologically advanced, even surpassing the North in some areas (by adopting a Meiji type constitutional monarchy)

I have the suspicion it may be connect to whatever reason people use sexualised anime children as avatars...? I also don't understand it.

I think it’s just that Japanese culture represents a very sophisticated antithesis to many western cultural pillars. Collectivism over individualism, incredible development of the aesthetics of simplicity and emptiness compared to the ostentatious and sometimes baroque western aesthetics, neat and tidy compared to cluttered, the fanatical emphasis on mastery of technique, or things that can’t be produced via shortcuts, etc etc. Overall I think the Japanese are viewed as much more disciplined and conscientious which is valued in the west. And a lot of these things seem like wizardry to Americans because we’re lacking the routines and building blocks that lead to it. In essence the Japanese are very process oriented, and Americans see the results and want them but don’t understand the process side of things as it’s not intrinsic to our culture. Yet the results are admirable… whether or not Americans would actually want to live the process that leads to those results is another story. That’s the gist of it I think.

[delayed]

So, I can’t honestly personally understand taking your shoes off in an emergency, however I am sure they have gotten very efficient at it.. I can say that if they didn’t it would cause damage to the home, many Japanese homes, especially traditional but also in general just aren’t built to take shoes. Tatami mats, and even hinoki floors despite being “hard” for a softwood, is still a softwood, so some level of genuine damage would occur. Again of-course versus the emergency in saving a human life, I’m not quite sure I can understand it.

I'm the same way but if I pass out in my house I absolutely do not give a shit about any of that and don't want the EMTs wasting time taking their shoes off to save my ass.

There's nothing unsanitary about it. The bottoms of your shoes simply are not that dirty unless you're walking through abnormally dirty situations.