It's more helpful to think of Communism as just another kind of religion.
People who ran Soviet Union had very little to do with leading people on the streets. They did had few squabbles with loyalists after they began their purge campaigns, but their extend is also exaggerated.
Ones who were the true loosers were the people who hid under the bed and thought that things will sort out (no civil war ever "sorted out" - one side loses, another wins.) And even bigger ones were those spend the civil war wailing and moaning for moderation and trying to dissuade others from even thinking who is right and who is wrong. Bolsheviks repaid those types with a lot of gratitude, those fools were first to walk in front of firing squads after a token expression of gratitude.
Very misinformed statement, don't even know where to begin. Red Terror was Lenin's invention. The whole leadership was a band of thugs. Lenin developed an entire philosophical theory of terror. These 60 millions were not killed overnight, true. The "night" lasted from 1917 to 1953.
After all, don't most revolutions involve a denouncement of the previous culture? For example, most Americans were British in culture, but they then shrugged off the trappings of that culture, choosing to rule themselves rather than to accept norms set by the rightful king and parliament.
Denouncement of religion isn't new either -- for how many countless centuries have religions (and sects of religions) been denouncing each other? Regarding tolerance, anti-religious secularists are the same as fundamentalists, except that they deny one additional religion. Probably even better morally, because they rarely call for killing those who disagree.