Most languages have a regulating body except for one (English) , Mostly because languages are fluid and new words come in and old words go out. Because most of the innovations come from Anglo countries (especially the US) most new words come from english. People will just use the english word and over time the language becomes english.
If you listen to YIVO Yiddish and Chassidic yiddish you will easily notice this, YIVO Yiddish sounds like a distinct language, Chassidic yiddish is more yinglish and over time it will become more and more english. The YIVO at least tried to make yiddish distinct (but is failing because nobody speaks yivo yiddish, they only speak chassidic yiddish)