All that money and he's still a mortal just like the rest of us. I wonder if mega billionaires like him have done private research on life longevity, cryosleep, mind-upload, etc. It's the only useful thing they can do with that much money that directly benefits them. Anything else (legacy, influence, children, etc.) doesn't benefit them when they're gone.
With all the billionaires we've had, the fact that no one is living unnaturally long or in some kind of cryosleep or AI simulation probably means one thing: It's simply not possible, and if it is, all the money in the world won't get you there.
As a result, extreme results in one or the other are not usually attained by people who do not have extreme prioritization of just one.
It is totally possible that a rare talented unicorn pursuing (and succeeding at) both goals simultaneously is needed for us to achieve radical life extension.