I don't think people praise notch for being a great game designer, do they? He kinda just kept doing stuff and hit it at the right time with the right game. We hadn't been subjected to the alpha funding model before, and that sale of 'promise' was still new and squeaky, and indie games hadn't quite exploded yet, right time, right place.
All games are copies and iterations on existing ones, EQ -> DAOC -> WOW for example, each added their own twist to the previous and improved upon it. I played infiniminer before getting minecraft and it just lacked something that minecraft has, that flavor and personality of the world.
Anyway I agree strongly with your sentiment but the fact is that the world doesn't reward hard work and knowledge and creativity. I have a friend working on a game with this pretty bad ass hand built 2d engine, he made it back before Unity/UDK existed and all that in c++ / dirextx. It is really kickass honestly, and the game play of several of his games is pretty damn good, a one man creation of a functioning RTS.
Though the art was off, he lost money/time to add the polish layer once the engine and gameplay was good, and the game sold basically nothing. That polish push is where the $'s are at, and always has been. The world always walks on the back of great engineers, and unfortunately I don't see this trend ending any time soon.