I guess those Chinese GPSDOs will eventually dry up ?
Maybe. Some of them come from domestic retired 3G/2G telecom devices, so they should keep for a while.
Also, the most failed part of Chinese politicians is that whenever they try to ban anything, it only annoys law abiding citizens and those who are determined to violate the laws still can find a way out.
There still ways to get used electronics to China, just at higher cost. They won't be able to get boatloads of eWaste, but they can still disassemble the valuable parts in original country and only smuggle them to China.
As long as Shenzhen remains the world's electronic supermarket, there will be a way to get things in.