I think the trend may well go in the other direction, and become more like shipbuilding. Due to reusability, we can afford to make costlier rockets, as they're useful for many launches. This may for instance mean the use of relatively expensive composite materials, such as in the BFR, which prioritises fuel cost above unit cost. Also, the efficiency of rockets generally increases with size.
Honestly, large-scale composites are actually cheaper per unit dry mass than metal 3D printed parts. Composites may be more finicky, but they're not necessarily more expensive in aerospace!
Carbon fiber composites are more expensive than stamped metal parts like automobile bodies, but if you're talking CNC machined or 3D printed metal parts, then carbon fiber can indeed be cheaper.
I think the trend may well go in the other direction, and become more like shipbuilding. Due to reusability, we can afford to make costlier rockets, as they're useful for many launches. This may for instance mean the use of relatively expensive composite materials, such as in the BFR, which prioritises fuel cost above unit cost. Also, the efficiency of rockets generally increases with size.