I've told Japan to fuck-off before, complained about selfishness and passive-aggression on the trains, and pointed out my low opinion of keigo. I'll try not to rehash that, but tell you a story, and draw my generalizations from it, and years of living here.
I'm one station from home and an older couple get on my car. He's not less than eighty, bent over and looks in some pain, nothing holding him up but his walker and the arm of his seventy-odd year-old wife. Guess how many Japanese get up. Go ahead. Guess how many Japanese look away. You got it: none and all. I get up, for which I deserve little credit: as I've run a half-marathon a few months ago, am half the age of that gentleman, and actually do it more for the sake of 'Gaijin bash'. As usual the Gaijin upstaging gets a few people to do the right thing. Someone gave the wife a seat.
It's not as if everyone in my Toronto gets up when they should, doesn't smash through smaller women in order to get on a train, and the like; however, you can depend on someone doing the right thing. Sure, in both Tokyo and Toronto a lot of people are dicks. On the other hand, if in Toronto just one in five people would have given that man a seat, and in Tokyo that is just one in twenty (and fewer if Gaijin are absent...), that is a difference of 400%.
The most important thing to know about Japanese culture is very simple: they are not more polite than Anglophones. They may even be less so. They are certainly more mannered, but that is no virtue. Being mannered means following the rules that are in place in society. It does not mean they are good rules, and it does not mean having any empathy. Of course just as many Japanese people have empathy as Anglos, but the rigidity of their culture makes it harder, and less rewarding, for them to express it, especially to 'strangers'. It's also worth noting that we might even get up ruefully, with little empathy, because our ethics do not allow us to indulge our selfishness. Fine, but the person who needs it more still gets a seat, right? If you are in even the most tangential of relationships with a random Japanese person, be assured that you will likely be better taken care of than at home; if you are not, you're on your own, chump.