This frequency of English localization issues is unacceptable

[Wanzzo]

Do you have a source for that?

I don't remember them ever promising more languages.

It's an old promisse. Made around when they launched HW (or even further back...)
If my memory serves, spanish and italian "with more languages to come" was the mentioned ones.
I am here since the 1.x version and listened to a lot of their Letter From the Producer. I think, the promisse was made in one of them. Well, not a "promisse", but an answer made by Yoshi when they read a question from the forum (this pratice were very common back then).