The overview does leave out that there is also a veterinary use high calorie "appetite motivator" variant as well (12 kcal per tube vs 6 kcal for the standard version).
When we took one of my cats in to pet emergency last fall because he had stopped eating his regular food, and was only minorly eating some alternatives we bought (baby food and other cat foods / treats), he gobbled 3 of those tubes down voraciously. Subsequently diagnosed & treated for FIP and as back to normal as can be.