Currently, person with highest amount of bitcoin in the world is Satoshi Nakamoto and he is the 12th richest man in the world. Can his number one spot be taken by some other person anytime soon ? Who can be that person to replace Satoshi ? Elon Musk ?
Most of elon's wealth is on his stock. I doubt he'd rotate all of it to bitcoin some day.
I'd say there will be nobody that can overtake satoshi's bitcoins holding except institutional investors which in essence owned by many people.
So far, I just can't see any billionaires out there moving their capital to btc out of the blue as an individual.