It's the same for a round for going through windshields, sheet metal, or hard barriers. For me, I just don't see those situations happening for me, therefore I don't pay much attention to those ballistic tests. For me, I pay attention to heavy clothing.
But keep in mind, the ballistics data just looks good on paper. We're talking small holes and small differences between loads and calibers.
I wish I knew more why these lighter rounds are being introduced and what problem they are trying to solve. I can only guess by the type of markets and advertisement trends I've been seeing in the magazines.