I agree. I will do side by side quite often when I'm programming or doing a specific multi-tasking work, but my "regular" browsing is fullscreen. I don't see why I would browse the web (single focused task) on the left or right half of my monitor, that just seems... silly?

I do not maximize some of my applications because i want to have several of them visible at any time when i'm working on more than one. I do maximize some other applications, depending on what i'm doing. I do not maximize the browser because i want to have the content i'm working with/looking at/reading in front of me (especially on the reading aspect since reading long lines is tiresome) and maximizing on a 16:9 monitor means that a lot of content will be at the sides.

Now combine the above with the fact that i'm using a ~23" 1366x768 monitor, the tendency of pretty much every site out there to use the window width as a means to differentiate between mobile and desktop sites and the stupid trend to use ginormous font sizes everywhere and you get an idea of how much i like browsing many sites out there (at least HN and old Reddit is perfectly fine). Well, i'm thankful that browsers have a zoom option at least, many of the sites out there are only usable at a 70-80% zoom for me.

But yeah, last time i had my browser maximized all the time was when i had a 4:3 monitor.

It's bewildering to you that people want to look at multiple windows at the same time? Really?

That's my feeling as well. I bought a large monitor with nice resolution and I want to run my applications at full size. Window tiling is nice but its also a distraction for me and I always seem to forget which app has focus.

And thus the overwhelming challenge of UX becomes clear. People like different things. I don't maximise any of my windows.