“Yiddish is one of them. It is no more a separate language than Yeshivish.”
1) I am familiar with all four, and let me assure you that English is closer to yeshivish than Yiddish is to German. (are you really arguing this point?)
2) yiddish is recognized as a language by many bodies, it has a regulating agency It is a bit absurd to try to argue it isnt a language
3) Even if it isnt an “official” language (whatever that means) I still don’t understand your point .