A very large portion of the Russian “olim” are gentiles with some Jewish ancestry on their paternal side. Many (but not all; many others among them didn’t bother to) of these Russian gentiles in Israel underwent a fake “conversion” by the Zionist rabbanut that justified it in the name of “nationalism” even though they openly acknowledged that these Russian so-called converts never intended to keep a single Shabbos, before the Mikva water dried off them, or to ever stop fressing the Russian delicacy of bacon.
As a result of a Beis Din, notably headed by Av Beis Din Dayan Avrohom Sherman who is Daati Leumi and was a visiting scholar at YU, ruled that all those thousands of so-called “converts” never were halachicly converted and all remain gentiles.
As such, these non-Jewish Russians are a perfect fit for the Reform movement, which itself conducts phony conversions and recognizes paternal descent.