They just pour the concrete on. There's no compaction or smoothing. So you don't get a flat surface. A "print head" that compacted and smoothed to make a flat surface would be more useful.
Like this simple curb making machine.[2] This is the size for making garden boundaries. A bigger machine with automatic guidance is [3]. This is making a mall parking lot. Both of these will make a nice, flat concrete surface.
I wouldn't call that an "actual house" since I don't think anyone lives there. But you can walk past it in the neighborhood. It looks nice. Iirc, the company building these has several lived-in houses in a community to get veterans out if homelessness, as well as a village where there was high-magnitude earthquake that levelled all of the houses except the ones that were built by them!
This might be one of those 'we made it look weird so everyone knows what it is and you can feel smug about owning it' things like stupid looking car prototypes, early electric cars (i3), white in ear headphones, recyclables, patagonia vests etc.