Sugary foods cause a crash after consuming them. So yes, there is a negative fall associated with it.
The thing with calorie restriction is if you eat all good foods that make you feel good, likely your "calorie restriction" situation occurs anyways. If you have enough of the good-feeling foods to not be in a state where calorie restriction is actually happening, you begin to feel bad (full/bloated). And thus, fulfill the scenario where "feeling bad" actually is again bad for your long-term health.
The two of you seem to be using different definitions of "shortly afterward". Two seconds after chocolate cake you feel better, two hours after chocolate cake you'll probably feel worse. Sugar affects different people in different ways, though.
The thing with calorie restriction is if you eat all good foods that make you feel good, likely your "calorie restriction" situation occurs anyways. If you have enough of the good-feeling foods to not be in a state where calorie restriction is actually happening, you begin to feel bad (full/bloated). And thus, fulfill the scenario where "feeling bad" actually is again bad for your long-term health.