I don't think it does. Both the articulation and the ground clearance claims are almost certainly nonsense. The ground clearance might be 'technically' more but you're comparing the point clearance below a live axle diff to basically the whole of the underneath of an independently sprung vehicle, so when fully articulated (assuming the cross-linked suspension concept like the Discovery has) the inside end of the compressed suspension arm is probably going to be very close to the ground.
The reality is that most of the live axle vehicle has much more clearance, which is obvious by looking at it, and is what matters when you are picking your way over hostile rocky ground. Look at the suspension geometry of something like the military Hummer (1/3 arm, 1/3 frame, 1/3 arm) to see what you need to engineer to give real clearance (and as far as I remember even those don't have spectacular articulation). I'd like to see the Defender with suspension fully extended and fully compressed to see what it looks like but the Utah photos and video didn't suggest a lot of travel.
Exhaust: yep. It is probably a casualty of packaging and is probably the best they could do (and in fairness, better than the D3 effort which was very vulnerable at its lowest point). When it ends up sitting on the exhaust bellied-out, it'll get squashed and either come off completely, or suffocate the engine.
The old suspension was durable simply because you can clout a live axle on a rock and get away with it most times. I don't believe the same is true of any independent suspension system and certainly not if it uses aluminium arms - in fact a relatively modest impact could write off the vehicle completely if it twists the attachment points. We'll see. The problem is, simulating killing a vehicle in three weeks on a 6 axis tester is basically bolting it to something that hammers the suspension up and down mercilessly. It doesn't rev the engine and drop the clutch, or bash the exposed bits on rocks, or any of the other things that happen when you're pushing the limits in real conditions.
Ultimately your last point is what has defined the vehicle - despite the brochure, it isn't really designed to be taken off road and worked all day every day, and if it was built like a Hummer it would be too expensive to produce and unnecessary for the 99%. All of that can be summed up in one question really: will the Army buy it?