I have to disagree. As far as I know, nitrous oxide is still favored by drag racers, etc, and is not used on GT or SCCA-like circuits. Personally, I'd like to see the GT series remain faithful to that type of racing. Besides, there seem to be quite a few arcade-type street racing games with much of that stuff.
Although having your engine blow might be interesting. I was wondering if that was going to happen the first time I saw the oil lamp come on in GT3, while on the Test Course.