For me this feels like robotics operating at the wrong layer of abstraction. It's like those old tomorrow's world programs where they show the robotic helper diligently sweeping the floor with a grass broom.
In car manufacturing robots are used to bolt and weld together stamped metal panels, this feels more like someone designing a robot which would be given a flat sheet of metal and using hammer and dollies forming the complete panel to be attached to the car.
In short, if we ever see a major change to automate housing construction I expect it will also come along with significant changes in construction methods.
The change is already there, prefab build techniques lead to construction companies keeping everything in-house - from crane operators to plumbers. The building is split into parts that can be built in-house and then assembled on-site - the aim is to have the structure with a roof on it as quickly as possible, since that makes you more independent of weather for finishing it. Especially for warehouses and facotries it's really impressive.
It's the difference between trying to take the factory to the site and just taking the parts to the site.
Also, as far as I understand, 3D-printing concrete does not give you any way to construct larger buildings, where you need pretensioned and reinforced parts...
You would need to build a tent like scaffolding that you can still work in, e.g. with a crane. That would be a non-trivial thing to design, put up and maintain, especially if it has to withstand stroms without damaging the building etc.
It is simpler to just put the house there quickly.
In many ways this is what much of prefab is. Building is carried out offsite by robots, and humans just assemble panels onsite. However, this reduces the adaptability of the building, increases transport and storage costs and complexity, and creates new issues (apparently prefabs can be at higher risk of fire).
Construction is one of those things where the process is much less regular and perfectly-repetitive than outcomes would suggest.
In car manufacturing robots are used to bolt and weld together stamped metal panels, this feels more like someone designing a robot which would be given a flat sheet of metal and using hammer and dollies forming the complete panel to be attached to the car.
In short, if we ever see a major change to automate housing construction I expect it will also come along with significant changes in construction methods.