On most monitors today you can still have 120 characters and see 3 or 4 side by side tracks including the filesystem in another track.
I also like to have one monitor turned to 1080x1920 for text editing and consoles. I'd never try to do a side-by-side diff on it, but it really makes you see just how many GUIs are downright wasteful of horizontal space.
I have 3 of those at my desk, 2 vertical and one horizontal. it's a popular system from what I can see.
(Also disagree about most people having 27" monitors, but I don't think that makes much of a difference)