Almost nothing has changed. I went to Japan last year (I travel there yearly) and rode the Shinkansen and even in 1964, still similar vibe riding it today.
I am absolutely mesmerized by this. As impressive as China's transformation has been since the 1980s, Tokyo's (and Japan's) transformation was arguably more impressive. Tokyo in 1945 was literally a wasteland, razed by relentless firebombing that left almost nothing intact. And then, not even 20 years later...this. A city completely rebuilt with a futuristic skyline, modern metro, and of course the bullet train: high speed rail, which the Japanese invented, built, and introduced to the world in 1964. Guts, determination, hard work.