I disagree, because if that was the case, the Panzer I, II, III, and IV would have never existed in mass production. The Panther was merely asked to merge the cost effectiveness of the Panzer IV, with sloped armor and a better gun than the IV. The Tiger I was in development in the early part of the war as to keep up with heavy tanks. I believe the Leopard would have been developed because of the Panther I, II and smaller E Series tanks. The E-100 and Maus were only designed because the Soviets were building bigger and heavier tanks, the Germans needed something to quickly counter that of course.
