Why is the argument unconvincing to you after you've just provided a bunch of evidence as to why Japanese people aren't engaged in politics and there is no opposition here?
I disagree specifically with the framing that the “the population and the country suffers greatly because of this” as it was demonstrated that mass political movements would never be allowed to exert control over its politics. It’s an entirely rational response to a sham democracy. The country (now) suffers greatly as a result of the course the U.S. set it on by subverting its democracy to protect its own interests.
As someone who has a decent grasp on Japanese culture, I think your take is too conspiratorial. The issue is simpler than this. Japan has an extremely hierarchical society and authority must be respected. This isn't a great combination, especially when combined with a severely aging population.
Young people have very little chance to enter into politics or gain any traction at all. There is almost zero chance a 75 year old will vote for someone in their forties.
Combine that with the natural tendency for some to a lot of corruption among politicians and it's just a perfect storm of stagnation, corruption and vested interests, there is absolutely no US involvement required.
This comment continues to be an entirely ignorant of the country’s modern history, which belies the claim that you have a decent grasp on Japanese culture. I recommend you spend some more time reading and less time making Orientalist claims of no substance.
