I'm not sure I agree with the premise myself, but I find the argument plausible: if it goes into a new charitable organization today, that's $10B off his taxabl

I'm not sure I agree with the premise myself, but I find the argument plausible: if it goes into a new charitable organization today, that's $10B off his taxable income this year, whether or not the money goes to actual efforts this year. If he directs donates the money later, then he gets that exact amount as a deduction later. Given that he's stepping down as CEO this year, the difference between a $10B deduction on his taxes this year and the same amount of money deducted across multiple future years when he has less income can be substantial. (This argument assumes that he intends to spend $10B on charitable donations at some point in his life anyway; it's not an argument for why spending $10B is better for his taxes than not spending it at all.)