He's been saying that for over a decade now. Back when he started he was worth ~40 billion. How is he giving his fortune to charity if his profits are far outpacing his donations? This is their way to impose the idea of the Altruistic Billionaire™ on the masses so we don't eat him and his billionaires friends alive.
If any of them gave a fuck, they'd do something actually notable. Finance affordable housing, build a non-profit insulin manufacturer, buy back land with endangered ecosystems and preserve them. Any number of things you could think you might do with $113,000,000,000 to help the world, somehow is always "the wrong way to go about it" to them.
They don't want to give that money away, they want to invest it as hard as possible to ensure it lives forever. Bonus points if you think they're like a rich Jesus along the way.