It is a great question, but it's like jumping on refactoring: you'll solve all the problems that were obvious with the old solution, but introduce new ones that

It is a great question, but it's like jumping on refactoring: you'll solve all the problems that were obvious with the old solution, but introduce new ones that you didn't think of that were already solved by the old one. Basically, "thermal blocks", which is mostly what's used in construction in areas where they are used (Europe, rather than filled-in bricks) need to be modified to accommodate imperfections: you need half bricks, third-bricks, and they are easy to make on the spot. For automated construction, you'd have to have a bunch of these pre-made, and the larger the block you are building with, the more types of those smaller ones you'll need. These blocks are also relatively simple to put electrical and plumbing installations in (it's a lot more demanding to make "channels" in concrete than bricks). Anyway, block construction is way cheaper than eg. gypsum board construction for interior walls in Serbia, and other than taking a lot more space, being heavier, and requiring curing time, it has a bunch of better properties (acoustic, thermal,...). The price not being high is actually the reason this is not further improved. Filled-in bricks are mostly used for decoration of outside walls these days (and usually as plasterboards these days), and as far as paying for things go, humans will happily pay the most for good looks!