I agree with Zahava’s dad. Yiddish once upon a time was a great unifier of Jews from all over Eastern Europe. Now, English achieves that same end. The difference is that people who still speak Yiddish, but who do NOT have a good command of English, do not benefit much from the MANY, MANY wonderful seforim that are written in English. Artscroll is Greek to them, secular education is a wash, and they appear uneducated, which sometimes works against them in the business world.
And while there are exceptions to every rule, the main reason Yiddish became a “universal language” for Jews, is that for Eastern European Jewry it was a necessity in order to be able to communicate. That necessity is no longer as great as it once was. Most people here speak English. Hebrew is Loshion Kodesh, and that is what our Avos spoke. BTW, not all Jews in Europe spoke Yiddish. Many spoke , Hebrew, Ladino or the languages of their places of birth.
Since checks are signed in English, contracts are written in English, and most business (uless Chassidish to Chassidish) is conducted in English, it behooves all of us to recognize English as a major language of Jews, besides Ivrit. There was a time when Jews spoke Aramaic to each other, but as that necessity became less crucial except for learning Gemarah, its use as a conversational language dwindled. We are seeing that today, with Yiddish, as well. Yiddish was spoken by holy people, but it is not intrinsically a holy tongue, no more than English is. I apologize if I am offending any Yiddish speakers – that really is not my intention.