Direct trade has been implemented for quite some time already. What China lacks that HK still has is what others have said, a level of transparency and legal framework that international companies factor in. You may say as long as there is money to be made, they will come. But that has a ceiling where the costs will outweigh the benefits at some point for any corporation. Then things plateau and may even slide backwards. Let's not forget other countries in the area are not stagnant, they will vie for the business too. Chinese corporations are starting to stretch out to other countries but they will soon learn what works within China won't necessarily work elsewhere because the level of transparency and legal framework elsewhere will make their method of operation unacceptable. So until the day when all Chinese cities have the same level of legal framework and transparency, HK will still have an edge. As quality of life improves, people in other Chinese cities will naturally start demanding the same. Look at how the lack of food quality control, pollution control, and legal recourse would bring up discontent in other Chinese cities. Why do so many Chinese who can afford it try to find a way to emigrate? To protect their assets in places with stronger transparency and legal frameworks?
Beijing actually will have greater ease in convincing Taiwan if it affords more flexibility.
