Not that I care enough to have a dog in this fight, but it would be much less stupid to claim that the vehicle glass is bulletproof than to claim that the body is bulletproof.
For a body panel to stop a 9mm, it would need to be about 1/4" thick (assuming stainless steel). The average thickness of a body panel, depending on which panel it is, is between 0.5mm and 2mm. So your bulletproof panel would have to be 3x to 6x thicker - and heavier.
If, on average, 30% of a vehicle's total weight is BIW ("body in white", the industry term for all of the body panels, untreated and unpainted) and we assume that a CT weighs about 5000 lbs then to make it "bulletproof" would require an additional 2+ tons of weight.
Glass, on the other hand, can be made "bulletproof" through the use of polycarbonate which, between the weight of the thicker glass and the additional weight required by heavier motors, tracks, actuators, etc., typically adds about 400 lbs. in total weight to the vehicle.
All this is to say that claiming "he meant the body, not the windows" is a bit far-fetched.