And, was it Russia that expanded to the NATO borders, or were the NATO borders that expanded to eventually reach Russia?
The sovereign countries themselves must get a choice - if they want to join NATO, that is their right, and Russia shouldn't get a veto (nor even a vote) in that. Countries should be free to join/leave the "spheres" at will, not be placed there or given or taken.
And, actually, the whole reason why NATO is at their borders is the Russian insistence of their sphere of influence. If Russia agreed in practice that their borders stop where they are and that they won't ever poke beyond them, then their neigbours wouldn't need to even consider NATO.
Uhh, no.
https://en.wikipedia.org/wiki/Enlargement_of_NATO#German_reu...
The belief in Ukraine, however, was that Russia was an ally, did not pose a threat and therefore Ukraine should have not seeked NATO membership. That assumption proved to be wrong now.
If anything, we can say that the current sanctions and other have been somewhat effective in deescalating violence, and if the west would have pulled back, then we'd have Ukraine dismembered by now through increased direct Russian military involvement.
Nothing "sets back" Russia to cold war mentality; they have never left it, won't will without a regime change, they won't stop treating the west as their enemy and they will aggressively (re)take the now independent states we let them to.