Always ask, I do have to say that Yeshivishe school has very fine, erliche girls. I didn’t bring up the story to criticize them, I just mentioned it because I was puzzled that they left it out but it proved to me that Yiddish is a language to be reckoned with as Chassidishe can say they have their distinct Jewish loshen.
Chareidy levush today did not originate from the time of the giving of the Torah…the styles first showed up by the non-Jews and was tweaked and adopted by Jews. That makes it Jewish, it doesn’t have to the fashion that the Yisraelim wore 3000 years ago. Same with the Yiddish language and foods Jews adopted from Europe or the Middle East, they become Jewish when they are adopted by a large eidah of Jews and repeatedly used for centuries, it became part of our identity. Regardless of how and from which language the Jews spoke in mitzrayim originated, if only they spoke it then it is became a Jewish language which set them apart from the Egyptians.
There are over a million Chareidy Jews with distinctive levush, Chassidishe, Yeshivishe, Sefardim, Yemenites, all who learn Torah. Regardless of the Torah learning, actually because of Torah learning, Chareidy levush sets us apart from non-Jews and reminds us that we are Ivrim and we are different. Jews should be able to be identified as Jews, that is part of being a Jew.
Jews were are Ivrim, we are apart and that is what keeps our identity strong so that we don’t assimilate. We can’t only learn the Torah, we have to live by the Torah with a Jewish lifestyle and one aspect of living a Jewish lifestyle is with Shem, loshen and malbush.