Now that you've dismissed Jewish self-definition, follow through by doing the same with that twentieth-century invention called Palestinian self-definition. First, though, set the whole topic aside and unpack nationhood into its components. All of Jewry until the Western Enlightenment, and the eastern-Ashkenazi and Mizrahi communities long after, had those components: language, law, literature, custom, culture, and even calendation, cuisine, and so on. I left out religion to show that Jewish nationhood existed, and exists in Israel, almost irrespective of religion. Now back to Palestinian nationhood. Its only substantive characteristic is self-definition, which you contemptuously deny to the Jews. Intellectual slop indeed.
The MW version of the genetic debate has reduced itself to one of those Israel-only "tests," like the right-to-exist "test," the gotta-be-perfect "test," and the you-promised-in-your-Declaration-of-Independence "test". Since Hasmonaean times and really long before, you find Jewish continuity at the national level even in dispersion -- in language, law, literature, even cuisine, and very much in consciousness of the Jewish national homeland and its borders, its climate, its topography, and all the rest. All of which concurrent with and part of religion. This is really what the Palestinians are up against -- professing a superior national identity to the world's champions in national identity.