I'd argue while perhaps they are examples of brutalist functionality, the wikipedia, reddit and HN offer a very nice UX and a simple, easy to learn UI.

HN/Wiki/Reddit don't: break the back button, take forever to load 1000 JS/CSS files, have broken "infini-scrolling", or even break when JS is disabled (well, reddit kinda does now).

Compare that to the majority of over-engineered SPA-style webpages that employed many, many front-end engineers and UX designers, and Wikipedia, Reddit, HN as well as old-school Gmail and FB start looking amazing.

Man oh man do I miss old Gmail... that was a great interface. I exclusively use FB on mobile, no-js mode.

Web brutalism should be the new hotness.