I agree. If they were 3D printing the concrete itself, I'd really be impressed.
There have been computer guided cranes doing that for decades...or at least the technology was there. A crane would pour fast drying concrete in concentric rounds ot the wall layout. One dried before the next was applied...very quick. May have been brought down by building codes, or just generally not cost effective.
I think there was an article (posted here) some time back where they actually did that - 3D concrete printing...China?
Not the whole structure/house, but main parts of it.
The only plus I see here is that molds can be produced with undercuts and the like that cannot easily be made by regular injection-molding processes.