[dirtyid]

Concrete = fast and cheap for post WW2 reconstruction. Which built up excess of labour / expertise in concrete construction that also spread abroad with post war emmigration. It's still the only economical choice for many regions. Not everyone has access to cheap, renewable lumber.

[mc32]

Concrete is useful. Large imposing structures poured in lace like a slurry wall doesn’t make sense. As a component of the structure yes, but not as used in typical unfinished concrete of that style. Steel and glass is cheaper, easier to maintain and has more flexible design. Plus it doesn’t look dystopian.

[dirtyid]

>Steel and glass is cheaper

If memory serve, it wasn't at the time. There wasn't sufficient industrial capacity for steel + glass post war to address scale of ongoing construction demands. Building form work out of wood and pouring concrete from local aggregate was cheaper in terms of labour, materials and logistics. It became self reinforcing with economies of scale as concrete supply chains popped up regionally. Which is building science in a nutshell, do what makes most economic sense at the time. Usually limited by transportation costs. Ergo cladding eventually replaced by cheap light weight building envelop systems due to increase in global trade and sourcing from Asia.

IMO applying dystopian to Brutalism is an label applied after the fact due to various cultural factors. The style itself was continuation of modernism. Of course modernism since inception has been a friction point between academia and popular sentiment. I do think many architects did delude / post rationalize concrete aesthetics to a degree, in no small response to fact that they had to work with it out of economic neccessity. Architecture school is very good at brainwashing students who entered due to love of classical aesthetics into embracing modern aethetics, because there just aren't much opportunites to build outside of dominant building systems of the era. So designers learned to love and celebrate concrete.