I agree. I remember feeling bored towards the end of my stint because conversations were getting trite. You basically repeated the same conversation with different colleagues but at different times because you are kinda conditioned by those conversation phrases so prevalently used in the culture.

As a teacher though, I was impressed by the precise standardisation attained by all educational authorities in the country. Like you said, a kid from Hokkaido could transfer mid-way into a school in Kumamoto and have no difficulties catching up with the curriculum because he would have studied the same things back in his Hokkaido school. I guess this conformity is stifling but for a nation that stakes its fate on collaboration, maybe having everyone on the same page at any one time is what they have always known in order to survive