A calorie derived from a carbohydrate is the exact same as a calorie derived from protein. Are you talking about more caloric densities of different macronutrients? Aka, there's more caloric density in fatty foods vs proteins, for instance?

Kinda like with running. Our hearts have no pedometer. It just works however hard it needs to for however long. The numbers, paces and such are things we add to gain insight into what that performance means. Calorie counting is often also the first introduction many people have to what their macros are like. And there is some wisdom here, around individuals and “calorie quality”, but you can ultimately still use calorie and macro counting as a baseline measurement to start understanding your body. I should caveat, when I say calorie counting I mean, tracking key macros too: protein, carbs, fat, fiber, etc.

Yeah, It's starting point. if it would lead into Macro and micro nutrients that would be great.