There is an old saying that no posture is bad unless you get stuck in it. The problem is that the thoracic spine often does get stuck in bad posture.
Deep Pressure Massage to the Low Back – Forward Head Posture
The neck and head do not contribute to the generation of pressure, so head and neck posture should be whatever is most comfortable and least stressful. Forward head posture, a common postural distortion imbalance pattern that occurs is caused by a flexion of the head and neck.