No, they aren't technically grilled cheese sandwiches. Taking a slice of bread out of the fridge and putting any kind of cheese on it isn't a grilled cheese sandwich, so why would a bagel be one? Most people also eat half of a bagel at once. And they eat them fresh or toast them. They don't grill or pan fry with cheese. So.. it's not grilled.. it's not a sandwich.. and there's an argument to be made about the cheese part as well.