Neither the consumer nor a repair shop will have the 3D printer to do that, and it would be almost as expensive as buying a new bike anyway (after the labor).

Neither the consumer nor a repair shop will have the 3D printer to do that, and it would be almost as expensive as buying a new bike anyway (after the labor). Worse, economy of scale means that you could just buy a new frame from the manufacturer for less than making one yourself. So in practice this option boils down to "throw the bike and/or frame out (scrapyard) and buy a new one."