I don't think it's that crazy for the language reform to make it through, seeing as the entire political system has been reshaped into a pseudo-American democratic structure for instance. With the emperor going out of fashion and the governance of the country being overthrown, I think it would be the perfect moment for other cultural shifts as well. Had the timing coincided with the introduction of computers (which famously struggled with languages like Chinese and most Japanese) a few decades later, I think the plan would've succeeded.
Most of Europe inherited the Latin script from Christianity, which was spread with less than peaceful means. It took more than a few short years, but it certainly altered culture.
Japan had a parliament since the Meiji era (first elected in 1890). The Macarthur occupation changed quite a few things, but less than most people think.
Most of Europe inherited the Latin script from Christianity, which was spread with less than peaceful means. It took more than a few short years, but it certainly altered culture.