Yes, but not because of DNA, but because they worshiped foreign gods.
and the descendants are not Jewish.
That's a non sequitur.
To say that descendants of Jewish mothers and gentile fathers are Jewish, but not visa versa ... I don't see that. It's merely some rabbi's interpretation. Or parsing, as you call it.
Nor do I see that the reason Esau was not chosen was because he took a gentile wife. So did Jacob. Issac's family were the only people of the promise at that time. Although they were Jacob's cousins, neither Leah nor Rachel were daughters of Jewish mothers or fathers.
Moses took at least two gentile wives. A Midianite, as I recall. And a Cushite.
Sure, Ezra was just “some rabbi” doing an “interpretation” when he kicked out the (now) Samaritans.
I think I’ll defer to the 3500 years of Judaism rejecting your nonsense as to how to interpret their laws.