But why is he a rock star, as you claim? Because he's spent much of his career marketing himself (along with his team). He's squeezed every single drop of blood out of the publicity rock. He also has a persona that leads to popularity - his folksy cliches, his bizarre comments, etc.
In his eyes, he's the Cowboys. He's the face of the franchise. So he markets himself as such. It's why he's never met a radio show or TV show he won't go on. But it's why he won't hire a GM. It's why he's still petty about Jimmy Johnson. He is the one that has to have the success. He's the one that when people talk about the Cowboys winning a conference title or SB, he's on the tip of everyone's tongue when they look to give the credit. He's popular because he has cultivated a persona and linked it with the franchise.
Jerry certainly isn't popular because he's put out a dominating product on the field for his fanbase.