He was given the training and knowledge needed to seize power in the KGB, but it wasn't until the USSR fell that he was able to amass enough wealth and notoriety to execute the attack on his own people; which cemented that power via the demand for a false sense of security. He played and continues to play the exact same "strongman" role that every Republican presidential candidate since the 50s has.
One doesn't need to have experienced that to know
exactly what those principles are. They're the same principles held by Elon Musk, the Koch brothers, and every other billionaire on the planet.
Naturally. Corrupt oligarchs aren't gonna change their tune just because you give them a new economic system to bend to their will.
Stalin was a product of the authoritarian left, but that doesn't mean he can be considered a proper Socialist/Communist by the textbook definition of the word. And that's because he never truly redistributed anything, but instead concentrated as much wealth and power as possible into the hands of the fewest people possible.