There are two different things here: what non-Jewish citizens of Israel identify as, and what their functional status is. The first is a component of the world’s most intractable conflict; the second is a question of nationality in the most basic sense: citizenship, identification on passports, etc.
The second sense is the one I’m interested in, and in that one there are plenty of non-Jewish Israeli nationals. They have every right (and plenty of cause) to not identify as such, but that’s the situation as it concerns citizenship, voting rights, etc.
TL;DR: nationality gets used with at least two different meanings in the I/P conflict; one is intractable and the other is straightforward. The straightforward is worth remembering, because far-right Israelis have a vested interest in eliminating it and imposing an ethnic definition of nationality.