That's the other thing about the CLI vs GUI debate. It doesn't only ignore the fact that you can use both together, but that some applications are neither CLI nor GUI. Yes, they have GUI versions, but emacs and vim are fundamentally not GUI applications. They are, let's speak it, full screen text mode.
Full screen text mode is not a CLI. There are editors that run in a pure command line. The most famous is ed. When vi was invented, it was a big step up from ed, but it wasn't a full replacement because it required full screen text mode.
Full screen text mode is certainly not a class of GUI. It doesn't require graphics. It may borrow concepts from a GUI, like pointers, menus, even windows, but it isn't graphical because it doesn't require the operating system to have graphics capabilities.
Full screen text mode is what we were using before GUIs took off. For certain tasks, it can be as usable as a GUI. It does, however become redundant when you have a GUI, hence vim and emacs get upgraded to GUI applications. The CLI, then, is the survivor, and full screen text mode gets written out of history.