> All that pouring and sawing and drilling and slathering of raw materials to do one-off designs for houses that are then filled with standardized ikea furniture which fits the custom room shape poorly.

Well, IKEA does have a joint venture with a construction company to make prefab apartments.

https://www.boklok.com/about-the-BoKlok-concept/ https://medium.com/@bartholomewhearn/the-flat-pack-taken-to-... https://www.youtube.com/watch?v=UwvvcgoHC9w

> Manual labor is too costly for such a bespoke approach.

Not in the US were there are always people willing to swing a nail gun to feed thier family.