Something like https://www.youtube.com/watch?v=CtYRfMzmWFU could be a happy medium. Shapes that must be 3d printed but forms that are less fluff and more function.

This is pioneering work, saving money in material and fabrication costs is something that will happen in the longer term when the tech is more mature.

This is a technology demonstration, not an example of super high efficiency. It also took much longer to make than it would have taken to make it in a more traditional way.

That said it still came in rather competitive compared to the alternatives, which says quite a bit about how manufacturers of such structures normally charge.

Having a welding robot run for 6 months straight will hardly reduce fabrication costs. Given the price of MIG welding wire it's also dubious if you could reduce material costs.