You are correct, there is some mixing and matching in this conversation no doubt.The OP was talking about posture over the ball...not talking about tilt.
Posture is interesting. I was always an activate-in-the-stance guy. But Carpenter, who W=W mentioned, Rizzo, Bellinger do things pre-pitch and then get activated and 'postured' as the pitch arrives. I like that feeling too sometimes, it makes you a bit more relaxed. But for most young hitters, that would be just one more thing to mis-time