Earlier quoted context omitted.
This is not really true. The amount of physical activity you do absolutely influences both your shape and your health. Also, we do have more sedentary lifestyles then typical 1960 person. Just in terms of how much you walk during the day, we are already not moving.
You have moved the goal posts. Exercise has a positive effect on health, yes. It does not have an effect on whether you're fat. That is down to food intake. That is what the poster was actually saying.
Also, I said "influences both your shape and your health". I did not moved goalposts.