I’ve seen a point made about concrete 3d-printers for building assembly: you can make a structure with them, but such structures are nowhere near a finished building, for most building uses, because you still need things like wiring, plumbing, insulation, windows, things like sinks toilets and light fixtures, etc. Maybe you could get around this by making prefabricated modular sections in an automated factory that a machine can put together in various configurations, but this will be far less flexible.