GA is certainly changing rapidly. But, I suspect that it has a lot to do with the decline of regional Australia. There just isn't the traffic going to country towns anymore. And the freeway structure is better and cars are better. Destinations where it was clearly more efficient to fly are now better done by driving.
And bank runs are dying. And freight is more commonly done overnight by road.
And a chunk of the traditional charter in things like Navajo's is now done in subcontracted private jets.
Skydiving is a good example of developing a product that appeals to a market the aircraft facilitate. But people sign up for the experience, not the flight. Too much of the GA debate focuses on aircraft as the end, not the means that facilitate another purpose.
A revival in GA requires a new vision.
But I disagree about a public campaign. The public don't care. GA is irrelevant to 95% of the public. It could go away and not many people would care.
But that doesn't change the fact that CASA is a dysfunctional organisation that is not fulfilling its charter. 3 decades or more ago Dick Smith got focus on CASA's predecessor with his book "Two years in the Aviation Hall of Doom" 2 decades ago Boyd Munro achieved real leverage via " Air Safety Australia". Bugger all has been achieved since.
Australia has a system of government that only reacts to pressure points and only consults with peak bodies. The AOPA is doping GA a large disservice because while it is recognised by Canberra as the peak body for general aviation, the government will not pay attention to other groups.
The best thing GA could do is get an aggressive, agitating, lobbying peak body.
At the moment GA's best friend is the senate estimates committees via senators like Xenephon, Fawcett, Nash, O'Sullivan and a small number of others. They seem to be the only ones making any attempt to make Skidmore and other senior regulators accountable. They are briefed by a shadowy group of anonymous industry figures. They should be briefed by an industry representative body.