His torso is NOT too far forward (not even a "tab" too much.) He is doing a low-bar back squat and his torso is
in exactly the position it has to be in to keep the bar centered over the foot. (And, yes, the position it has to be in to generate proper hip drive as well.) A high-bar, Olympic style squat will have a more upright torso and less hip drive, but that is NOT the exercise he's doing. He is an outspoken advocate of the benefits of the low-bar vs. the high-bar squat. Critiquing this video for not being a good example of an exercise he's not doing is just inane.
You ought to actually read some of his many--easily accessible, interesting, and clearly written--writings on the subject. The book
Starting Strength especially, but also his many articles (some available in various places online and a bunch collected in the book
Strong Enough?. In fact, he recently wrote an
article on
exactly this topic (Low-Bar vs. High-Bar Squats) the explicitly addresses many of the questions brought up here (you need to subscribe to the CrossFit Journal to get it, but it's cheap).
You might find this drawing (of front, high-bar, and low-bar squat positions) helpful in thinking about the mechanics of it all.