I know they don’t because michael broyde had to write a giant article to be ‘melamed zechus’ on all the MO women who don’t cover their hair.
Sounds like he followed the lead of the Aruch HaShulchan.
Regarding Yiddish, from Wikipedia:
Yiddish (??????, ????? or ?????, yidish/idish, literally “Jewish”; in older sources also “Yiddish-Taitsh” (Judaeo-German)[3]) is the historical language of the Ashkenazi Jews. It originated during the 9th century[4] in Central Europe, providing the nascent Ashkenazi community with an extensive Germanic based vernacular fused with elements taken from Hebrew and Aramaic, as well as from Slavic languages and traces of Romance languages.[5][6]
I don’t know how either Yidden speaking it (English) or being sourced from German (Germans?) makes a language “holy”.
You probably have a better argument that Arabic is “Holy”, as not only is it similar to Aramaic and Hebrew, the Rambam (as well as others) also wrote many Seforim in that language.