That's not Brutalism, that's pure classic modernism. Very Corbusier.
I'd say it's both. If you get away from the heights and walk around the base of the buildings, it's totally Brutalism - straight-up shaped concrete, nothing to decorate but the shape itself. It's also remarkably walkable and sociable. It feels like a space rather than an obstacle. (I credit part of this vibe to the Somali community, who are strongly self-policing and don't tolerate dangerous gangs of young men in their space)
https://upload.wikimedia.org/wikipedia/commons/9/9b/Riversid...
The colour does remind me a bit of a Mondrian, but I think it should be removed from the earth just as one would remove mercury-contaminated soil.