The question is how much money does one need?
The problem is not that the answer provided would suggests a large number. Millions, billions.
No matter how large a number it might be, we could redesign the world to accommodate it.
We could design a world in which everyone could be rich.
The problem is that the answer to the question how much money does one need is infinity. No limit. Infinite greed.
That is why we cannot solve our problems.