> It’s fascinating still to read, for example, Hertzl’s (Sephardi on his fathers’s side) commentary about this specific issue.
I personally wouldn't take my source of knowledge about Yiddish from father of the movement whose whole ambition was to abandon the Yiddish world.
> To be accurate, Ashkenazi jews don’t speak Yiddish they speak German. There was a cultural disconnect between these two groups themselves. The term oestjuden for example was used pejoratively.
Sorry but this is plain wrong again. A fusion language of German and Judeo-Semitic languages emerged from around the region of Germany at some point, the earliest writings of which are dated about a thousand years ago. This language spread and came to be known as Yiddish. The 18C Jewish Enlightenment (Haskalah) and Moses Mendelsohn in particular derided this Germanic 'jargon'. Where the Haskalah spread in Central and Western Europe, Ashkenazi Jews abandoned Yiddish for the major languages of their hosts - eg High German, French. In the east, especially Poland, where Jews tended to be much poorer and derided by the rich Jews to their west as 'Ostjuden', Yiddish remained the language of Ashkenazi Jewish community. and so it was until the Khurbn (Holocaust/Shoah), Stalin's post-War liquidation of Yiddish intellectuals and the State of Israel's only recently relaxed hostility to the language and culture. Ashkenazi Jews who migrated to America eventually felt the need to abandon the language too. And that's how a language almost died.
Except it didn't, because religious (Haredi) Jews, who represented a small minority of Jews pre-WWII, had too much at stake in Yiddish - commentaries, writings, the Tzenereneh, teachings - and didn't feel the same need to assimilate as secular Jews. So today the vast majority of Yiddish speakers across the world come from the religious tradition, including the one Israel.