No one has pure ICAO airspace. The US is different to Canada which is different to the UK which is different to ours which is different to the US etc etc. Every country has implemented variations of it (and can quite freely do so) so that it works for them. Why can't we? Sure we copied the US system, but it doesn't have to be the same. Even you Dick admit that, because you want to tack bits of ours onto it. This mantra that they don't do it that way overseas grows a bit thin when no one does it the same way. A lot of other countries have a lot more controlled airspace, but they need a lot more ATC and infrastructure to do it., Canada, probably the most similar size wise, needs twice our ATC plus 700 FS staff to run theirs. The US, 15000 ATC. I reckon ours runs pretty lean already. It doesn't seem to be raining aluminium because of it either.
Chinese cadets learning in Canada are going to go home and fly in whatever system China has. They will adapt. Same as when they learned here. It is not the airspace (or how much radio chatter you may or may not have to listen to) we have that is causing GA to struggle. Way too much energy and time is being spent on an issue that is superfluous to the big picture.