Wait, how is Warren Buffett nepotistic? He's giving the vast majority of his wealth to charity. He gave his kids each $17.5M to start their organizations, and then donated like $5B total to their organizations once they proved their management skills. But he pledged to give away most of the rest (almost $100B), and has already given away about $50B (latest pledge is 99% of his assets).
I really don't see him as nepotistic, he's pretty much the best kind of billionaire.