Joseph, please remind me, what language did Hashem create the world with? And for your argument Yiddish is holy because it is the common language… Of COURSE it is the common language! Jews living in Ashkenaz for centuries and you think that they will not pick up some goyishe language? That had been good for them then, but now?! Some things need to evolve when Jews travel to different places and come into different periods. And I am not saying that Jews need to be “modernized” like the haskalah, but rather I am saying that the time when Jews spoke different languages (i.e. Ladino, Yiddish) is totally gone.
Now is the time that Hashem is gathering Jews to put them in Eretz Yisroel for the Jews to be united, and what is more fitting to speak in Eretz Yisroel, eretz hakodesh, than loshon hakodesh instead of loshon hakodesh/german/old polish/slavic. And don’t forget that everyone will call their own language holy. Sefardim; Ladino is holy. Ashkenazim: Yiddish is holy. Persian Jews: Dzhidi is holy. Turksih Jews: Krymchak is holy. And that is just a few examples.
Hashem has given Jews Eretz Yisroel, and He gave them Eretz Yisroel for them not to be in golus anymore, and to change the ways that they picked up from the goy nations. And not to speak loshon hakodesh mixed in with the language of nochrim in the place where pure loshon hakodesh is in the history of the land is a perfect example.