Nice list, though I'm pretty sure Mark Cuban has something way more than that $120 in bitcoin that he's revealed. I mean, it's still money, and it's just his ego that he's protecting here if he doesn't tell the masses that he has bitcoins apart from the $120 worth he has now. Even if he's worth billions due to his ventures and businesses, he'd still want to get some money in his pocket in some way or another, and bitcoin is an easy money for that role specifically.
Maybe they are just hiding that they are a huge investor of bitcoin to become modest about their investment.
Just like what Elon Musk stated, he said that he only have 0.25 bitcoin but I think that instead of investing all in bitcoin, he prioritized Doge coin investment.
This can be somehow made us hold for more because these billionaires can manipulate the bitcoin price whenever they want. This is a good information so that we know popular billionaires who value the existence of cryptocurrency in the market. I'm still amazed how Elon Musk pumped Dogecoin for a short period of time and everyone on reddit and twitter are updated on it.