Riiight...
You could say that of French too. The trouble is, French is very deficient when judged as English. French grammatical structures are faulty and unclear in an English-speaking environment.
Likewise for Japanese being judged as Korean. It is deficient, faulty, and unclear. The fact that it is an alternate is unimportant. Japanese is very bad Korean.
The point of a language is to communicate. If you can't communicate, you need to fix that.