I would not suggest that those using airfryers are not cooking, and I do not think anyone else has, but if you google anything to do with cooking times for airfryers, it always consists of a list of lumps of food and how long it takes to cook them.
I think casseroles, stews, risottos, benefit from long slow cooking. I put a venison stew in my slow cooker this morning and then went out for most of the morning. It slowly cooked for 4 hours and was dwkicious, As I said it is not a question of either or, I hve both, but I use the slow cooker more,