Of course, the attribution of causes to this is highly subjective and I expect every person to come away from the elephant with a different interpretation.
In my case, the very, very top down 'age hierarchy' culture was (and continues unabated) to crush any ideas and proposals that come up from younger and more competent engineers. In the last 30 years with Japan, I have met only a small handful of people that are willing to take input, let alone change direction, from someone younger than them. (a trivial example was a fellow company director of mine that was born 5 _days_ earlier than me. In 4 years working together, not once would he take anything I said seriously. Hmm...)
Give the number of excellent Japanese software engineers that I know, the burden of this "culture" is (to me) quite tragic on its impact slowing down national progress in an important global field. If anyone as ideas how to get around this, I would love to know and learn.