Earlier quoted context omitted.
You would be surprised to learn that history is littered with examples of the fickle preferences of one person impacting the trajectory of the human species. Also I'm curious why you think that a government is better suited at spending money. From what I've seen this leads to lobbyists doing all they can to curry favor and secure contracts despite the fact that they deliver a sub-par product.
"Great Man history" is a troublesome way to interpret the past and neglects many other forces that shape our society and planet: https://en.wikipedia.org/wiki/Great_man_theory
Suppose Constantine never converted to Christianity. Suppose Genghis Khan had been injured before conquering Asia. Suppose Louis the XVI had reformed the French government. Sure some other ruler would probably have embraced Christianity or some other ruler would have conquered Asia but history is fundamentally a sequence of events and minor changes, like a strong ruler in one place or another, can have massive downstream impacts.