For anyone who comes here without clicking the link, it's linking to a comment of the intern that actually wrote it. He provides some neat context as well. Worth the read if you don't mind being on Reddit at work.
Screenshot captured with phantomjs/rasterize.js and shrunk with pngquant.
https://www.reddit.com/r/todayilearned/comments/3zfadv/til_t...
Maybe this will help?
I found the dark screens fashionable in Linuxland and themes very hard to look at for a long time. Weirdly, now I code with Monokai theme in OSX and it is very enjoyable.
Perhaps the white background was easier when you weren't typing on two 24" screens and only had a 12" screen to peep into.