iTunes not separating files into Music and Audiobook top-level folders

I just added some music to iTunes, and noticed that it wasn’t sorted into the “Music” folder, as it normally would be. And I noticed that the last couple of audiobooks I’d imported weren’t in the “Audiobooks” folder either, they were just in the top-level media folder. After fooling around a bit, and unchecking and rechecking the “Keep iTunes media folder organized” option, iTunes proceeded to completely reorganize everything, moving it all out into the top-level media folder.

This isn’t the end of the world, but I always liked having separate top-level folders for music, audiobooks, movies, and so on, so I could easily see how much each category was taking up via the Finder.

I’m on the most recent version of iTunes, 12.8 I think. Does anyone know if this is a change that Apple made recently, or if my iTunes is confused somehow? Thanks.

Answering my own question: I had to go to File > Library > Organize Library… > Reorganize files…
Not sure why I had to do that. The library had previously been organized into subfolders, but I guess something got messed up in the preferences and undid it somehow. Oh well.