How the Saudis handle a thing should never be used as an example of whether or not that thing is any good. The KA-52 is at best as capable as the initial version of the AH-64D was, but the Yanks have 800 Apaches (and decades of experience using them, plus they are all being upgraded considerably) compared to the Russians only having ordered 140 (and have around 60 available now). The T-14 is still in the very early stages of its production, as evidenced by it breaking down at the May Day parade.
As for Ukraine, you seem to have not noticed that NATO's backing really did not consist of much - whereas the separatists had active Russian military assistance on a considerable scale, and were not able to defeat the Ukrainians; in fact all they managed to achieve was ensuring that what remains of Ukraine is now vastly less Russian than it was before the crisis started.