Wait until you try high speed rail in China. They're 10-15 years ahead of Japan.
China is pretty good, but the only place I've ever seen proper turn-up-and-go HSR is Japan. Tap your card or phone (NFC-F, because credit card contactless is too slow for Japan), walk on. If you missed the train you were aiming for there'll be another one 7.5 or at most 15 minutes later, so no big.
China has more high speed rail than the rest of the world combined.
1. https://www.railway-technology.com/features/the-10-fastest-h...
And tickets, specially in Spain, are very cheap.