The thing that a lot of people don’t realize is that when you’re selecting from a list, most people scroll up and down. For example, if you’re making a grocery list, you don’t write the selections across the page but rather down. Additionally that’s what we’re used to doing with our phones as well.
Same thing with websites, it’s just what our minds have gotten used to doing. So having to scroll left/right to select a library (especially if you have a lot of them) is something users aren’t used to.
