I was constantly running into this during drawing classes in college after having spent countless hours in Photoshop in high school. It’s amazing how firmly the Cmd-Z reflex plants itself as a reaction to making a mistake!
I’ve also caught myself yearning for Cmd-F when hunting for something in large chunks of printed text.
That's why traditional books (especially references and textbooks) have an index at the back.
I understood that as suspend. It still works! Who wouldn't want infinite time for video games/hobbies while time was stopped.
What else would it be? EOF on CP/M? I assume that's not what was intended since it is possible in real life (and the OS will do it sooner or later).