You would imagine that the switch to power to weight rule is for the purposes of allowing eco boost cars to be driven by P platers and reduce the abuse of turbo/super charged diesels.

Performance turbo charged cars, e.g. Silvia's, Skylines, WRXs etc, would and should still be banned under the new rules similar to how 350Z and M3s are banned although they are N/A 6 cyl (under Victorian Law).

I see no harm in banning high performance cars from P platers, been on enough touge runs to see the stuff they do. It's a good time to learn the fundamentals of driving and vehicle dynamics. There's plenty of time later on to enjoy Turbos and 8s.