The 'Brutalism' thing in a nutshell:

1. Designers coming out of art schools like ECAL, Gerrit Reitveld, etc. in the mid-2000s start bringing some of their experimental work into the small print magazine movement (mostly in Europe at this point) after print starts getting less scrutinised in favor of digital. See: https://www.creativereview.co.uk/the-new-ugly/
2. Hits NYC from Europe (to be fair people in scenes like RISD were always woke) when guys in publishing like Richard Turley bring the aesthetic into the mainstream on publications on Bloomberg Businessweek
3. More traditional (not product focused) design agencies/studios bring the aesthetic to the web after the fall of skeumorphism and the rise of web type
4. SF Tech bros who hang out on Dribbble finally take notice when these sites get posted on SiteInspire, steal the term "brutalism" to describe it since it doesn't look like a stripe landing page.
5. 'Brutalism' becomes a catch-all term for any website that contains an aesthetic nod to a design movement that didn't happen on Dribbble
6. Myself and others find this amusing and post snarky/snob-ish finger-wagging comments on DN

Also, see Aaron's comment below, this site falls much more under Swiss International Style than it does this so-called "web brutalism."