Wu Runqun still recalls the fishing village Wanning once was, nearly 20 years ago.Now in his 40s, in those younger days he had travelled there from his much larger hometown two hours away to see if he could surf.After that first trip to Wanning, on the east coast of China’s tropical island province of Hainan, he found it hard to stay away from the two-metre (six-and-a-half-foot) swells and warm 24 degrees Celsius (75 degrees Fahrenheit) water. Wu moved there in 2017.He was not the only one to...