Are these RUSSIAN HOORS considered Huwhite?

Except for the fact that whiteness is born out of outdated racial Darwinism that is itself horribly unscientific.
Whiteness can be culturally real, and that's valid enough. But if you say it's scientifically real, you've said too much.

>although the Slavs are more mixed with Mongols and Uralics
Not really the case for Western Slavs and even when it comes down to Eastern ones, it is mostly the Russians that are mixed. There isn't much Mongoloid, especially Uralic admixture when to comes down to Belorussians and Ukrainians, though nowadays there is quite a lot of Russian admixture which also includes the fore-mentioned Asiatic groups.

how did darwinism create obvious distinctions between human subspecies existing for tens of thousands of years?