I guess I'm missing the connection on those websites to Brutalist architecture. It seems more like they're bored with regular design, and want to be more experimental.

It reminds conceptually more of Emigre magazine [1] or Ray Gun [2], where the design didn't have to be "readable".

    [1] https://www.emigre.com/Magazine
    [2] http://www.davidcarsondesign.com/t/tag/raygun/