To a degree it might but that's why I differentiated between structural and functional abnormalities. It looks more like mild pectus excavatum. Chiro and even physical therapy aren't going to change the shape of his ribs and sternum. That's pretty much what his body is going to look like regardless of the amount of therapeutic exercise, stretching, or adjustments he'd receive in treatment. His chest doesn't look like that because of kyphosis/forward head/rounded shoulders. His postural problem is caused by his sternum and ribs being sunken in.....not much you can do about that beyond surgery. Just like with scoliosis, it can be structural caused by misshapen bones or functional caused by tight/lax musculature. Depending on the degree of the curve you can manage it conservatively, but with more aggressive structural cases need constant bracing or surgery to correct.
I've had plenty of patients that have George's type of posture in my 10 years of practice. Some get better, some don't. The ones that do show improvements don't have structural issues in their skeleton.