SawThe Light,
Never said it was because of not being a Boeing design.
Originally, the 747 was supposed to be a double decker like the A380, but their sumulations made them think they would be unable to satisfy PAX EVAC tests so the shortened deck came about. Interestingly enough, they did not know that much about area ruling and had no idea that the hump would make the airplane perform in cruise better than without the hump.
