There is a "skill" to everything, and my card making skill is probably a 3. It takes me some time to identify nuggets that will be long enough not to be trivial but also short enough to make good cards and salient enough to bother with. ChatGPT on the other hand is probably a 7.5-8 in making cards, and it can crank them out. On top of that it can suggest things that you are probably going to be tested on given the stuff in your notes that you might miss if you just created cards from the contents of your notes. If you have a famous teacher at a public university who teaches every semester for a big core class, it can even go far beyond that in ways that will surprise you.