When we think of capitalism we are usually referring to business. In other words, somebody builds up a business and then eventually makes it work after years and years of trial and error, mistakes, and learning.
A 16 yr old kid has worked hard at basketball, but that's it. And he suddenly goes from making nothing to 6 figures. Along the way he has not developed any business acumen, financial literacy, or even how to do a simple budget. He is not prepared at all to handle that kind of money because he's never had to worry about managing it. He's just a highly skilled employee.
I understand the argument about capitalism, but to paint with such a broad brush just doesn't work.