[namenotrequired]

I wish this was how all billionaires thought. I hope it's how I would think, if I were a billionaire. They probably think[1] however that there's realistically little they can do even with their billions to significantly lengthen their life within their lifetime. So they'd rather make their life better instead.

There might also be some (perhaps cultural) selection bias - people who want yachts try to become billionaires, people who want to improve the world focus on improving the world themselves rather than on becoming rich.

[1] I wrote "realise" first, but I have no way to know if they are right or not.