The overenthusiastic amateurs are the ones tripping themselves up as they don't know how to negotiate. "My way or the highway" is the style seen time and again.
And there we have it.
The designation of airspace in Australia is not on the basis of objective principle, but on the basis of “negotiation”. Private citizens “negotiating” with the Department of Defence for a reduction in the amount of airspace tied up as defence Romeos. (Heck, it would be great if they were reduced to just triple the size of what the US Defence Force considers necessary for an equivalent amount of military aircraft and operations.) Private citizens “negotiating” with bureaucracies who couldn’t care less about private citizens who, after all, exist merely to be regulated.
You ask what to replace C with. As I’ve linked the LAX chart, let’s compare the airspace around e.g. Long Beach Daugherty (LGB) with e.g Albury Australia.
Wikipedia says LGB had 1,451,404 “passenger boardings” in 2010.
Wikipedia says Albury had 285,353 “passenger numbers” in 2009-10.
Although this may not be an
exact apples with apples comparison, you may safely assume that LGB is quite a bit busier than Albury.
Now compare the dimensions and classes of airspace around LGB and Albury. Try Coffs and many more...
The air must be different in the USA, or the aircraft built differently or the pilots trained differently, such that the yanks manage to move more aircraft around with ‘lower’ classes of airspace with smaller dimensions than Australia does, without it raining aluminium as frequently as you scaremongers predict.