Also for me if I go to crossfit after workday ends I don't get cravings the rest of that day. If anything I want to go to sleep instead of eating candy in front of the TV.
So this isn't really 3 separate unrelated changes. Also at least in my experience, people tend to regard high protein things as the "energy dense" part of a meal - the problem with a lot of carbohydrates is they're not very filling.
The biggest problem with exercise is it's an awful way to lose weight - you don't burn that many calories, it makes you hungrier, and then your body optimizes to burn even less calories as you do it.
Who are these people? I suspect a lot of people who are overweight/obese and taking GLP1 drugs have very little to no concept of proteins role in their body composition. Essentially all a GLP1 drug does is modulate down your hunger (and you get full faster). That does not give you any of the tools or skills to create a diet or exercise plan. Both of those require intentional planning, research, skills, and time. They're definitely 3 separate things.
Getting on tirzepatide made it trivially easy for me to get back to a better diet, start exercising, etc. I do have to force myself to have an extra protein shake to hit my macros, though.
You're asking folks to make three separate changes: start exercising, change their diet to add protein, and use GLP1s to reduce food amount. And reducing food amount already goes against adding protein, so whatever protein they were getting is going to get cut even further.