Having spent time in quite a few 'iconic' Brutalist building, my experience is that they're frequently terrible. Impressive looking, but deeply unfriendly to their inhabitants. There's one where it sometimes rains indoors because the venting and vault-ceilings are so poorly executed. It's still lauded as great architecture.
Well, on the other end of the scale we have McMansions[0] - although part of the critiques[1] also feel like architect snobbery to me at times.
1. Badly-designed and badly-built (as in, objectively not up to some verifiable standard) homes built with the look of better-built homes but none of the construction quality those homes have.
2. Houses built by the newly-rich on small lots, in contrast with the houses inherited by the old money on larger tracts of land.
The inevitable and, perhaps, deliberate conflation between the two senses is pure class warfare, of the "Established upper class striking against the newly arrived" sense.
If you have a different style of window in every fitting without a strong aesthetic tie then you've just raised the build and maintenance cost of the property for no reason except cargo cultism.
Buildings with flat roofs and piss poor drainage in the West of Scotland (rains a bit) are held up as timeless paragons of the style.
This tells me there is a massive disconnect between architects and normal people.
(EDIT: There is quite a lot of Brutalist stuff I like but there is a lot of shit decaying ruins that I'm repeatedly told are brilliant that are most certainly not)