Lutke and Zuckerberg are billionaires. It is literally impossible for them to run out of money. Their grandchildren's grandchildren will be born incomprehensibly wealthy. They have won at capitalism.
But they also captain their first large enterprises: do they know what they're doing? Can they transition these firms into businesses that will endure? Or will they capriciously chase shiny objects while they waste the trust and goodwill of investors, the people who work there now, and the people who will want to work there in the future? They might have seeded the garden, but it took thousands of smart people to build it up, and it takes a constant supply to maintain it.
A new CEO will probably be rich, sure, but not "endow a historical dynasty" rich, and might know how to take a successful company and reposition it for the long term. Maybe the younger guys can do it. But it would just be for vanity at this point.
