You know that Bill Gates isn't one guy doing all the work all by himself right?
Really? No, that's a total surprise to me.
The point is not who does the work. The point is who decides which path to take. And from what I've seen so far, Bill is anything but a hands-off manager. His education project is the way he thinks it should be done, and his malaria foundation does business with pharmacy companies that he holds stock in.
It might just be that he listens to his experts and then goes on stage selling their proposals as his ideas, but given his history with Microsoft and Windows and DOS, I doubt it.