What could exist is a world based on economic democracy, where no one becomes rich or powerful and everyone has to work together because society is structured to prevent anyone from taking power for themselves.
An economy where the stock corporation is replaced by the worker cooperative -- still an independent business operating in a free market of goods and services, but governed democratically by its workers -- would be much closer to that reality. No one would be able to amass much personal power. And any power amassed would always be held in check by the democratic structures that granted it. A world like that would do a much better job of preventing the accumulation of personal wealth way beyond need.
I think the closest to this, in current practice, is the German model, where workers have at least a say in the direction of their enterprises (not sure about ownership). It seems to be working out really well for them.
In a well regulated capitalist environment, those drives are yoked in a way that the paths through which you become rich and powerful and sexy are the same paths through which you improve the lives of others around you.
In a poorly regulated one you get dupont and enron, but show me a silver-bullet government theory and I'll show you an unrealistic fantasy.
>A mindset of "greed is good" and "it's okay to be self" does not even try to understand the difference between "need" and "want"
You're assigning that. Honestly I don't think most of Ayn Rand's critics have read her books.