GenZedong

I see what you mean. Most of my exposure to the hypothesis (other than the aforementioned Zionist tropes) is from Cold War era non-Zionist Jewish sources, and they really didn't deal too much with the Yiddish thing. I believe the idea of the constant movement of peoples, in those tellings, explained why they ended up north and west of Khazar land for the same reason the Magyars and others ended ups in similar places. The main up-shot of those sources, at least in my reading, kind of goes to your final point, but in a different way. The idea being that the peoples in the Steppe were always a fluid amalgam of people and there were home-grown Jewish influences there that became a cultural seed that developed in groups in the area that sought to neither ally with the Christian world to the west and what was developing into the Persian/other empires and Muslim world to the east. So that reading of it goes that essentially no one has mythic ancestors in any one place because the version of history during any time period where one would posit a homogenous genetic group stayed "pure" from others is, at least with respect to Eurasian and African history, false. As those writers point out from the genetic (albeit, genetics as they existed a few decades ago) perspective, Jews generally are more genetically similar to the populations they live with than Jews from disparate places have genetic commonality with each other. I definitely agree none of this matters with respect to the current genocide of the Palestinians, but the modern politics overshadow the almost mundane aspect that I am more curious about regarding the movement and interactions of peoples from Eastern Europe to Central Asia prior to and after the Rus came into the picture.