Mansa Musa was the richest man in history, and much more "liquid" than Elon.
Few of these modern rich people are quite as rich as they are portrayed. Remember that most of their "wealth" in tied up in the shares of the companies they founded/own. If Elon attempted to access all of his wealth, the required share sales would tank the stock price, wiping out a majority, if not virtually all, of their supposed wealth. It does provide leverage in terms of the debt to which they have access, but even that is limited.
Anyone who believes that Musk, Bezos, or Zuckerberg are more consequential that the myriad other "players" on the world stage do not fully appreciate the "competition" that is going on at that level. Most of these folks are but one miscalculation away from ruin.
Elon has accomplished some amazing things. He has demonstrated amazing buffoonery. In short, he is quite human.
In the grand scheme of history, Elon is but a blip.
There are much scarier characters out there, in my opinion.