Actually Elon Musk is not the only rich famous person who supports crypto more than fiat. Mark Cuban, Robert Kiyosaki, some rich politicians etc. Robert Kiyosaki said that "I'm not betting on Bitcoin, I'm betting against economy. I'd rather have Bitcoin than dollars right now".
When there's a good opportunities for sure there are many billionaires behind it, some are quitely monitoring the market and
continue enjoying there benefits without revealing their names.
You mentioned those known names who are behind this industry and for sure there are more rich and famous who don't want
to have media exposures unlike Musk.