I remember this from way back in the 00's as part of the Web 2.0/semantic web era. I was a big fan of Dan Cederholm's design work (https://simplebits.com - he did the design for the site).

I do like the principle of trying to use semantic html, but I don't think that things like this ever got the kind of mass adoption that would give them staying power. Still a nice nostalgia trip to see it here.