Pinnacle because it was a simple, functional website back when it started in '95. Back when UI design didn't cost millions of dollars with MBs of crap JS clogging things up.
Come off it. Adding a few lines of CSS to give things reasonable contrast and spacing is not "millions of dollars". 2005 called, they want their jQuery back.
Concrete web design? What does that mean?
I guess you mean the site is simple but that's not what brutalism is.