This is a stupid example, really.
Who is able to eat junk food and maintain a caloric deficit? And why would someone do that? That is, you eat little food that makes you very hungry and also will you have nutritional deficits. What is the goal of that?
People who eat garbage eat a lot of calories unless you are an idiot who wants to do a study and a documentary to prove a point that does not occur in real life.
The ideal is to eat little and clean, and to do some exercise. It is the most difficult thing to do because in our culture we do not accept a life without pleasure, goals and adrenaline. If you want to eat a lot and clean, you can still have problems, if you want to eat a lot and dirty and also not play sports, you will be more screwed. If you are an athlete and you take gear, you will be more screwed. If you are sedentary and eat garbage and take rec drugs and alcohol, you will be more screwed than anyone.
There are only a few cards and some general factors, play how the hell you want, but do not try to fool yourself or others.
When I was a kid I ate what my mom cooked and snacks I was not fat. As did my cousin. Then we had 2 more cousins who did the same and were fat.
Not every thin kid eats a healthy diet and everyone knows this. Never met a kid that counted calories. I ate a bagel fruit, school lunch with snack food, mom's dinner, then snacks and ice cream as a kid, I was not fat
Now I'm old and healthy although I eat mostly clean now, and lean.
Point? I grew up eating shit wasn't fat and then didn't become a fat adult, jist like millions of others.
Ironically I was pretty fat for a few years of adulthood. That was when I was permabulking eating 5k a day of clean food trying to be the biggest strongest guy in the gym. Fat and strong and high bp and no cardio thanks to tons of force feeding clean food...
My main points
Most kids can eat normal kid diet and not be obese or grow up to be obese
Tons of adults many who do what we do get fat eating too much clean food
I prefer to educate people on diet esp kids than try and micromanage their diet like we are coaching them to be an athlete
People are fatter now because they are lazy and entitled and have too much technology, McDonald's has been around since I was born in the 80s fast food isn't to blame
Calories in vs calories out, yes clean food will limit hunger but not everyone is like us and has a big appetite.
A few slices of pizza satisfy a normal person. I want a pizza and a half. Hence why I'm someone who needs to eat clean where my cousin can eat pizza and be fine. It's all individual.