Bill Gates seems to have upped his media presence this year. I am seeing a Gates article in some stream or the other almost on a daily basis.
Bill Gates is financially involved in a large number of startups mentioned in the article. Good PR = more sales = Gates' portfolio is better off.
The other reason is a little more conspiratorial. There is a growing trend of financial populism where politicians are clamoring for higher taxes on the rich (70% on $10+ mil). I think Gates is trying to mitigate this movement by showcasing how he uses his wealth for the greater good.
He is right that a 70% top bracket won’t increase revenues by much.
Many people in his position would be looking to try and make the world a better place for his children. Bill Gates however is simply technically strong and wealthy enough to do this through more direct means.
> One estimate puts extra annual revenue from Ms Ocasio-Cortez’s idea, which applies only to incomes above $10m, at perhaps $12bn, or 0.3% of the tax take.
https://www.economist.com/leaders/2019/02/02/how-to-tax-the-...
He's so astronomically rich he's barely human. What could anybody do to affect him in a way that changes the things he could do with the money he has?