>He could have distributed (read: invested via donations and grants) more sooner.
The only way he could have done that is to sell the company, and using your definition, as soon as the company was worth more than he needed personally, he would have to sell it to not be a hoarder.
I'm pretty sure in that case the company would never have grown to what it is, as there's ample studies showing that founders, who know a business, provide more growth than letting outsiders run a company, when averaged across all companies. I'd suspect this is the case for this person also.
So your plan would have resulted in less total worth provided to humanity.
And, as I pointed out above, the only way to realize that value is to sell ownership - so now you've removed some cash from someone else to get ownership, given that cash to this owner, for a net zero change in cash available for society, with a likely less value add over time. This is why these ideas do not work economically.
Warren Buffet is a good example of this - he was far better at allocating capital than most (perhaps anyone), and when he dies the world will see that worth transferred to charity. Had he constantly handed it over earlier to less efficient capital allocators, there would have been less growth, since others are likely far less capable than he was/is, and there would be less total for the planet.