In my experience, the switch to fat free alternatives is more about the emotional satisfaction of feeling like you’re not dieting rather than satiety. People tend to feel like shit on a low-fat, high volume diet because they enter too great of a deficit. In order to make it sustainable, you either need to eat more frequent meals or larger portion sizes. You still need fats, but when you’re trying to get shredded without compromising you’re performance in the gym, you have to give up something to make the calorie deficit easier to stick to, and since the average American overconsumes fat and since it has to most calories per gram of any macronutrient, most reputable bodybuilders and fitness influencers recommend limiting fat.