What you said and what I said can be true at the same time.

They were for-profit and subsidized, but you still don't get into these fields to get rich, and other than Tesla and SpaceX nobody has. Even so, based on business fundamentals Tesla shouldn't have made Elon rich, he just happened to ride a broken stock market caused by state socialist market interventions in the wake of the Great Financial Crisis.

If Elon just wanted to get the highest numbers, especially at the time it seemed the best idea would be to head out and build a new Internet company. Given his showmanship there's every reason to think he could have founded some new company with unlimited margins that sold bits and bytes to people. Instead, he went with companies that had to manufacture difficult to manufacture things, heading into industries where margins rely not just on efficiently transporting data from point A to point B, but in building complicated physical devices -- an infinitely more complex, higher risk venture with much lower potential payoff in terms of profits.