You have to remember that the vast majority of this sub is under 30 and still thinks that making millions of dollars is the primary indicator of living a good life. You can't blame them. I was the same way in my 20s.
It's also worth noting that there are several sources that claim Poole is a terrible teammate and arrogant to a level that even professional athletes find obnoxious. So it's quite possible that he isn't "more successful in life than 99.9% of people", at least not yet.
Yes, he gets paid millions of dollars for playing a game he loves, but that has very, very little to do with leading a successful life. Think of the many athletes that also commit sexual assault, domestic abuse, or other violence. It should be pretty obvious that there is little to no correlation between wealth and leading a successful or fulfilling life. There's no doubting that he's one of the best basketball players on the planet, but to call him "successful in life" is a little shortsighted.