Native American tribes each have their own rules for tribal membership. The Choctaw, for example, unlike some tribes don't have a blood quantum requirement, but just require descent from a tribal member.
Imagine me a white person with no Native American ancestry at all, telling a white looking enrolled member of the Choctaw tribe that in fact they aren't really Choctaw. Imagine me insisting to anti-racist progressives that despite not being Choctaw myself, I'm really right, and Choctaw are wrong.
I think we know how appalled progressives would be at my attitude.
And yet I'm seeing Pro-Palestinian progressives claim that Ashkenazi aren't really Jews, even though Mizrahi Jews identify them as such.
Why, for progressives, are the rules different in the case of Jews? How do they have status to make ethnic determinations for one group to which they do not belong when they would deny anyone else that status in reference to any other group to which they do not belong?