We are talking here about people that we DO know. There are a lot of crypto billionaires we don't know about. And we never will. Take Satoshi as an example. He is a crypto billionaire and we will never know who he is...
Yes in crypto we couldn't know the real name behind every wallet so we couldn't know who are the wealthiest people in crypto.
I don't really think that the Whales would really anounce their name for publicity .
For me it is better to stay low profile rather than making some publicity because you could endanger your life and also your family members.