[hardwaresofton]

I have to say I didn't see the the comment in this light, and now I'm wondering if I'm under attuned or if you (and others who posted similarly) are over-attuned.

There's a very real truth to japan's generally law abiding culture and it's the double edged sword of homogeneity. "good area"s didn't signify anything about race/culture difference to me (I wasn't even thinking of foreigners/non) in the negative, but more about how the basic "shared programming" of japanese culture is generally tilted away from crime/disobedience/singular action and towards law abidance/obedience/group action. If you take a look at how certain systems are set up (online security, in person security, how paperwork is done, etc), it can only exist in a country with very tight cohesion which comes from very tightly held shared values (or at least the appearance of that), whether that's a good or bad thing.

I didn't see that the commenter was implying that the heterogeneous portion was responsible for all the crime, but just that the dominant culture was on average more lawful than another might be, and that since that culture was so concentrated crime in general was lower than you might find in other places -- reducing the need to worry for everyone who lived there.

That said, Japan definitely has that kind of insidious/hard-to-demarcate racism/classism/etc. Japan as I've experienced it is just really good at 'other'-ing groups of people in some way or another and you could see it as a product of the culture, their historically generally xenophobic nature (also culture, I guess), or some other things.