CrazyMTOWDog
You state
Please state factual evidence to support your statement
I can see why you don’t reveal your real name. Why aren’t you asking for factual evidence to substantiate that in a large jet, the thick part of the wing should be close to the fuselage and the thin part of the wing should be outboard?
The reason you are not asking this is that it is just plain common sense.
In relation to airspace, there are Airservices studies which show that the risk of collision in the terminal area is about 100 times greater than the risk of collision in the approach to that terminal area.
It stands to reason then that if you require C airspace where the risk is one 100th of what it is below, you would then need to step up to a higher category of airspace, ie. B, where the risk is higher.