Gorbachev was the one who ended the Cold War.
He took a look at the superpowers' nuclear murder-suicide pact and saw it was a dead end. He saw what it took for the USSR to keep a stranglehold on Eastern Europe, and walked away from all that. Perhaps he even grasped that the USSR had some deep internal flaws in its system, baked right into it from the beginning, which would rot it from the inside out - tried to change it, but too late. Maybe none of that would have happened if not slapped awake by things like Cheronobyl, but at least he saw that big picture, where ideological victory would be meaningless in a world that's dead.
Not any of the eternally greedy assholes on this side of the curtain ever managed this feat. Those same "leaders" of ours later re-wrote the narrative to glorify themselves, and used the lack of an adversary to whitewash all the problems that have turned the west into one big self-defeating swindle.
Yes, I'm sure the end of Gorbachev's days were filled with bitterness, not just for the bloody fate of the former USSR, but that after all the peacemaking efforts he made, it got disrespected and trashed by the west too. We are now back in open conflict, one that's more about betrayal than ideology.