Hi Galen, I am very happy for your friend and I understand perfectly his decision. I think there are people who think they are going to be eternal, or I don't understand why they only focus on work. That's fine for an age, but when the time comes when you know that you have already lived more years than you have left to live I think it's time to adjust priorities. When I hear phrases like, "people get depressed or die," I can't help but think how poor some people's lives are.
In my case, I'm a decade behind your friend. I have in my head, and I am working with him, a "retirement" plan that still has a few years left to be mature.