It seems like Monobook is the only skin whose styling matches all the boxes and tables used in articles. (Minerva makes a valiant attempt to restyle infoboxes but doesn't touch other elements like https://en.wikipedia.org/wiki/2020_Masters_(snooker)#Main_dr... .) It's forward-thinking, placing the search box in the sidebar where it doesn't take up valuable vertical real estate on widescreen displays. It doesn't try to shove controls in between the title of the article and the content of the article. It's even got a responsive layout for mobile devices!

I say they should have bumped up the font size a notch, added a max width option, and saved themselves thirteen years of redesign work. Web design truly did hit its peak in the early 2000s.