You guys are missing a pretty major fact: the car in GT Sport actually does have magic powers that didn't exist in reality.
When it actually raced, the GT-R LM NISMO had no hybrid system. That's pretty much because the original hybrid system as designed by a third-party was reportedly snake oil (it still doesn't exist) and the backup system Nissan planned to replace it broke everything every time it ran it, so Nissan disabled the system altogether and ran as a pure ICE car - but without the power available to either the LMP1-H or LMP1 cars it was obviously slower.
The original "Flybrid" system from Torotrak recovered power from the front wheels and stored it in flywheels. About a quarter of the total electrical power - 750hp, so around 185hp - went to the front wheels. The rest went to the rear wheels via a pretty mad portal axle layout. That essentially gave the car nearly 800hp at the front and 550hp at the back, out of corners.
When it became apparent that this system would never materialise, Nissan postponed the car's race debut and reclassed it from 8MJ to 2MJ, replacing the 4WD hybrid system with a battery FWD hybrid. That system destroyed every gearbox Nissan showed it to - although the GT-R LM NISMO's gearbox was a bit complicated so, no huge shock. When it came to Le Mans, Nissan ran the car without it.
The car in GT Sport has a functional hybrid system, which the real car never raced with. I think we agreed last time this came up was the 2MJ version, which the car did at one point actually use in testing but never made it to a race, not the 8MJ version which also would have driven the rear wheels if it ever actually existed.
Notably, the GT-R LM NISMO was actually as fast in the speed traps as the top LMP1-H 8MJ cars, because far from being a "half-baked" design, the principle (based on those huge air tunnels either side of the cockpit, only possible because the car was front-engined) actually worked. It's just the car never had the power of the others because of a hybrid system Nissan was sold that didn't exist and a much weaker, rapidly cobbled-together replacement that destroyed gearboxes, and it lost seconds in every corner exit while it fought up to speed.