When a normal person gets a lot of money (like by winning the lottery) they do not become like Elon or Bezos. A third of lottery winners will declare bankruptcy within five years. The smartest ones will put their money in an index fund and enjoy a nice retirement.
For people with actual ideas, there are lots of ways to get funding- venture capital, government money etc. Having your own money to spend is nice but that's not the overwhelming advantage everyone seems to think it is.
On the other hand, doing the "actual work" as a scientist/engineer is not particularly difficult. Each individual engineer is responsible for a very small and well-defined problem that can be solved using skills that are taught at thousands of universities around the world. If any of them were to quit, they could be easily replaced with someone who's just as good.