but Russia hasn’t been able to get the kind of [material] support from its allies that Ukraine has

It hasn’t needed to. Ukraine wouldn’t be a functional state at all by this point were it not for the tens of billions of dollars in aid as well as all the military equipment slowly depleting the west. Russia on the other hand, has been doing quite well in holding it’s own economically despite the sanctions and in holding the literal defensive line against all the NATO weaponry. It’s a nonsensical comparison to make.