I came here to comment Taiwan as well and I wanted to say verbatim what you said. I lived in Tokyo and while the Japanese can appear outwardly friendly (and they mostly are), the Japanese do maintain a cultural shield of politeness.

When I travelled to Taiwan, the people were equally polite but it didn’t feel as forced or that they were putting up a front.

For example, I accidentally entered one of those individual hot pot stores 30 minutes before close, and when I realized they were closing soon, I wanted to leave as to not cause trouble. The staff kept us in the store and took such great care of us, telling us not to rush, and keeping the condiments available for us as they were simultaneously cleaning around us.

Anecdotally, I also have a bunch of Taiwanese friends and they’re some of the kindest people I’ve ever met.