Honestly, because they can't speak a lick of English.
Unless you have a manager/mouthpiece, you can't have your top champions unable to communicate with the main audience.
I give Andrade credit since he learned English. Asuka and Nakamura still haven't learned to speak it without sounding ridiculous.
Brock speaks perfect English and he ain't spoke nary a word. Build a Japanese stable, with a Japanese interpreter. They are the female tag champs, and Intercontinental champ. Add 1 or 2 more it'll work.
