Yes, GA is still pretty restrictive in HKG, but the more you gently push against the incumbent system, the more it leans.
For instance, when individuals in HKG saw that the PLA would only allow weekend flying from Sek Kong (the only licenced airfield in HKG apart from the international one), they started up rotary flying. The Aviation club saw that it was working so bought their own helicopter less than a year ago, and started flight training. They are not quite into double figures of PPL(H)s yet but they have decided to buy another helicopter. The demand is there.
The GA in HKG is a vibrant as you make it. If people come to fly, the club will buy the kit. Perhaps the constraining factor is weather, with industrial IMC drifting across from the factories in Guangzhou most days. It is a serious pollution problem that restricts flying.
Perhaps the most hopeful aspect is that the border will become more penetrable. At present if you want to fly into China the bureaucracy and fee structure makes every flight an expensive epic. It will change. I would surmise that we will be able to fly over the border on training flights, without a landing and return to Hong Kong, in less than two years.
Why? Because that is what China wants.