Of course he doesn't come up personally with, say, rocket engine innovations. But what he does is orders of magnitude more valuable - motivating people, making good high-level decisions (because he's smart and knowledgable in multiple areas such as engineering, design, marketing), getting the right people work for him and being very hard-working.

Being a good CEO is just way more valuable than being a good individual contributor, because it multiplies the output and growth of the whole company.

And ego doesn't really matter that much in the big picture.