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.
The problem (IMO) isn't your suggestion that marginalized people be taught to use and understand General American, it's that you characterize speaking Black English as a pathology.
It can be important to speak the prestige language if one wants to advance in society, but it's not a medical problem to speak a local dialect. Would you advise an aspiring London barrister from Yorkshire to see a therapist or watch some YouTube videos on RP?
As a white man with a strong Southern accent - when I don't suppress it, which I do in professional settings - I assure you that looking down on someone because of their dialect is not solely determined by skin color :)
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.