this is what happens when several generations of a former highly patriarchal, honor-driven culture grow up under a demoralized, devastated, and utterly defeated generation of patriarchs.
post WW2 Japanese culture is nothing like what it was before that. It's like someone hit the reset button. The children of that day were more or less on their own when it came to shaping modern Japanese culture. Technically brilliant, of course, but what was once Japanese culture is no more. now their children are in charge....and this is merely another part of the decline.
Think about how we, in the US, consider our WW2 vets as "The Greatest Generation." In Japan, it's the complete opposite. (Well, it was during their time, anyway). I wouldn't think that current Japanese look on them as an embarrassment, but considering how they were raised as Japanese and as Japanese soldiers and what happened to them, they very much feel that way about themselves. Consider that any non-soldier citizen was trained to be a soldier at the home. A nation does not easily recover from that.
All notion of Japanese masculinity is completely gone--it does not exist as it was, as it was completely defeated.