It was not my intent to say that it's not possible to lose weight when you have a thyroid issue. Rather, my point was that your weight loss/gain is not determined solely by the amount of food and activity in your life. You can maintain the same amount of each and suddenly start gaining/losing weight because of a thyroid issue; or some other reason. But yes, the fact that there _are_ other factors doesn't mean you can't do things to combat/mitigate them. You're right, there.
I still managed to lose 40 pounds via calorie restriction and absolutely no change in exercise.
I basically did strict keto for 6 months. CICO is a real thing. Even hypothyroid, you're not going to gain weight if you aren't intaking the calories.