I'll start off by pointing out the fact that both the front and rear differentials are open, meaning that effectively 100% of the torque will be transmitted to the wheel with the least amount of grip (to put it extremely simply.)
I'm not sure how turning traction control off effects the electronic brake distribution of the Subaru Vehicle Dynamics Control system, but there are two big things I notice:
1. With the rear right wheel in the air, the car still moves forward, maybe because most of the torque is applied to the front wheels by default and not enough is sent to the rear, nor is it needed to support getting over the hill.
2. With the front right wheel spinning, neither does traction control appear to cut power nor does VDC appear to be braking the front right wheel.
Also, it may be a Subaru, but it's an economy Subaru, and while the layout may be more conducive to better dynamics, is it really better than any other cheap AWD system out there? To know we'd have to see this same test performed on a slew of other AWD vehicles.
Finally, how many FWD vehicles do you think would pass this test? That's a real question, not a sarcastic Subaru sulky response.