Screens, somewhat counterintuitively, used to be wider. Because they were not on handheld mobile devices. Then we had the menubar and nested dropdowns, suckerfish, etc. It was an exciting time to see a menu, you were never quite sure what you were going to get - I believe there are positives to learning curves for power users.
But I digress. 三 means 3 in Chinese. It doesn't take cognitive load. Why does a hamburger? I really am curious.