That's no surprise to me - monitors are so ridiculously wide these days that it's impossible to ignore the need to limit the length of a line of text. When you're working at 1680x1050 you can kinda ignore it, but with 1920 or more horizontal pixels, text needs to be broken up into columns, and you've also got enough horizontal space to have two windows side-by-side without feeling cramped.
That has always surprised me about Wikipedia. So many articles on recommended line width, height, font, etc., and Wikipedia gets away with just one style rule (font-family: sans-serif). Never heard any complaints or noticed that it was bad typography.
Yeah they have more style rules, but disabling them doesn't visibly change anything so they're the defaults.