They also had this legitimate grievance against the Germans who'd just knocked down 60% of all standing structures in what used to be called the USSR.
Eventually Stalin died, a series of apparatchiks of questionable talent followed, and in the end we got to see Boris Yeltsin on TV writing decrees that dismantled that structure and put the Russians on a different path.
Maybe that could have happened earlier with a deeper Allied advance from the West, and maybe it couldn't.
A lot of that blood could have been avoided if they had a different ruler....The Soviet Union won, in spite of Stalin.