I think that saying calories are the key to weight loss is like saying altitude is the key to flight. If you want to fly, the key is to keep your altitude up. It is technically true and even useful in a way, but the truly difficult part is how to keep your altitude up.
Run a caloric deficit and you will lose weight, guaranteed. Just like if you maintain altitude above the ground you're flying. But how to run a caloric deficit day to day is the trick. You can look at it and say "just eat less", but eating is such a deep, fundamental drive that it's never that easy.
Satiety is a completely different issue. I have no problem with those who differentiate, but there are legitimately a lot of people who think the laws of thermodynamics do not apply to human biology.
Trouble is that there are a lot of people who think it's reasonable to tell an alcoholic to just stop drinking. They tend to be the same people who think that "just eat less" is good weight-loss advice, and they often have alcohol and weight problems.
Run a caloric deficit and you will lose weight, guaranteed. Just like if you maintain altitude above the ground you're flying. But how to run a caloric deficit day to day is the trick. You can look at it and say "just eat less", but eating is such a deep, fundamental drive that it's never that easy.