Rome lasted between 400 and 1500

I don't think the timeframe is any good at identifying the failure. I'm not sure that Rome has seen as many historical events as the USSR: two world wars, television, nukes, space, computers to name a few. The correct answer here is that we can learn from experiments such as Rome, Paris Commune, and the USSR. We can't learn from Putin though, assuming we both don't want to build a relatively stable authoritarian proto fascist regime.

Stalin never stood in a bread line

Realistically, how do you imagine that? Because I can't: you've built an authoritarian state with one party on the top, the country is not in the best condition. right now. There is no place for martyrdom here, you are obliged to rule the state while the things are as they are. I do not agree to shit on Stalin/Castro/Mao for exercising more lavish lifestyle than the common people. I can agree to shit on them for creating the system where they are the center of the country though.

On a side note, do you know the story of Vasily Stalin? He was Stalin's son and he did not have such privileges.

There seems to be an inherent vulnerability to revolutionary political actions to co-option by charismatic strongmen.

Historical irony here is that Lenin himself discusses this in "What is to be done?", giving the example of Napoleon if I'm not mistaken. He's all for democracy though.

staying out of everyone's personal life

The first thing Bolsheviks did, was cancelling the persecution by political reasons (being gay included) and legitimizing abortions.

Overall I see that although you identify as a right winger, we don't have that different world view and how the world should be. I very much appreciate you being honest. Such threads make me love humanity more