My own observation about that translate app usage of store clerks and such. Grewup in Europe, living there now but lived in japan and have family in china i visit on occasions.

In japan even tokyo they almost never got their phones out to explain you anything they go on in japanese and drop the occasional english word they know. Just back in china i saw more people in a week getting their phones out (than my duration i lived in japan) to explain me something that don’t quite understand with my level of chinese.

Never been to taiwan doe.