Why is milk substitute powder divided into high-protein acidified milk powder and high-fat acidified milk powder?

Milk substitute powder is not a kind of it, why is it divided into high-protein acidified milk substitute powder and high-fat acidified milk substitute powder two kinds? Who has experience in this field, and what is the difference and significance between the two in application? Is there anything worth noticing? Different combinations of energy and protein have different values in different periods, sometimes focusing on energy and sometimes focusing on protein.