Go try dramatically changing your weight and see how it makes you feel. For the record I've never been obese, I'm in excellent shape and lift weights ~5 times

Go try dramatically changing your weight and see how it makes you feel. For the record I've never been obese, I'm in excellent shape and lift weights ~5 times a week. When bulking, eating enough calories to increase by weight by 25% requires significant effort. Similarly when I have do my cuts I find it incredibly difficult to get down to 10-12% body-fat. My body clearly has a weight it wants to be at, and deviating from that requires a significant mental effort. I imagine someone obese trying to lose weight struggles the same way I do. The body wants to be at a certain size, and forcing it to change is difficult.