Stalin was not acting much differently from certain Czars who came before the 1917 Revolution. That was what absolute rulers did in Russia. Communist Russia was not much different at all from Imperial Russia. There was just a name change and some face changes, but that was it. The cruel aspect of governance in Russia goes back to a combination of static and superstitious Byzantine culture and Mongolian totalitarianism.
Yes, Stalin was a latter day tsar.h His idol was Ivan the Terrible, one of the most ruthless tsars in Russian history.You're right that the Russian government was totalitarian in nature. It goes back to the Mongols to the tsars to Communists.