Something I think a lot of xians don’t get is that while Judaism and Tanakh are absolutely essential to xianity and it making any kind of sense, Judaism in no way needs anything xianity has to offer, nor is modern rabbinic Judaism dependent on the existence of xianity. We exist entirely outside of and independent of xianity and Judaism (both as it was before the fall of the Second Temple as well as modern rabbinic Judaism) would have continued just fine without xianity. If xianity somehow disappears from the earth entirely, Judaism will still be here and will still make sense.
On the other hand, if Judaism and all of its texts were to disappear, xianity is no longer intelligible. And that is what I mean when I say that xianity is parasitic on Judaism. This is not a mutual or symbiotic relationship, no matter how hard xians seem to want to think it is.