That doesn't disprove the point. Sure, the most famous actors might not be the best in the world at acting, but this is true of many fields. Is Bill Gates the most skilled programmer in the world?
Bill Gates is famous for being a businessman, not a programmer. People know him because he's rich and led Microsoft - not because of the code he wrote. I think there's a pretty good argument that he is among the best businessmen in the world.
