Japanese Characters in Permalinks- OK?

My friend says that I better not be using Japanese kanji (which are basically the same as Chinese characters) in my Permalinks. I publish in Japan to a Japanese audience, so international accessibility is not that important. Even so, people in other countries say they can navigate the site just fine. Here’s an example of one of my permalinks:

https://www.go-eigo.net/授業料とスケジュール/

all it says at the end is ‘class schedule’. The short link is

https://www.go-eigo.net/?p=325

which takes me to the same place (I assume the short link is the true directory and whatever I’ve written instead is an alias).

I figure in this day and age when everything is multilingual using kanji should pose no problems, and despite what it says below, I doubt there are many servers left that can’t handle double byte characters. I would prefer that my customers refer to Japanese, as they are, Japanese, and not to a transliteration.

Am I good to go on this? Thanks!

“If the double byte character is not in the server’s (IIS 5.1 on XP Pro) code
page, it is not possible. i.e. if the double byte character is in Chinese
while the server is an English server, no dice — it’d never work.”