One tiny little point: they weren’t “indigenous” when they got here and replaced the indigenous population.
There is growing evidence that there were “indigenous” peoples here who decended from the european Solutrian migration from the end of the last ice age (30-50K years ago). The Siberian immigrants overtook the fewer decendents of the early migration and in some cases intermarried but they pushed out the existing population that preceded them nonetheless. That is exactly the reason why they demand that any studies of remains earlier than 15K years ago be squashed. They were the real first invaders.
Indeed—They should more appropriately be referred to as Native Russians, or something like that.
They didn’t replace the indigeous population. Else their descendants wouldn’t have the X-Factor gene sequence.