Not trying to stick up for the 911 but here are my observations. The 911's tires were garbage as we can see from the ending while the GT-R was using R compounds. The GT-R was set up to win. Badly worn street tire vs R compounds. Just look how sloppy the 911 was, running off line a couple of times and braking way too early for some corners. The ceramic brakes won't help if you got no traction. At the track, tires is the most important factor.
The GT-R is a great car but too much hype........plus I don't care how fast a car is, it's no fun trying to turn a 4000 pounds.