Chinas High speed rail has a 97% coverage for cities with a population of at least 500,000. (160+ Cities). (Including standard rail brings it to 99% of cities with 200K, 180+ cities). As you say, China is absolutely massive and that size makes this reach even more impressive. If Japan has better rail coverage, it's not by much.

Okay? Youre comparing Japanese technology that hasn't been built yet to established Chinese technology. China has successfully tested a 1,000KM/h Maglev...

China has transported 1.46Billion Passengers this year (as of may 2025) on pace to surpass the over 4Billion Passengers last year. I've only seen estimates of around 450M for Japan last year (though finding Data on Japan is more difficult due to their corporate divisions and not speaking the language)

Sources:

http://wap.china-railway.com.cn/english/news/202505/t20250527_145536.html

https://english.www.gov.cn/archive/statistics/202412/06/content_WS675248bac6d0868f4e8edb50.html

https://news.cgtn.com/news/2024-08-06/-China-s-1-000-km-h-maglev-train-completes-demonstration-test-1vQhnqCxUw8/p.html