what he means is who ever in power, his words are official. For instance, China is taken by the communist who comes from the North, speaking mainly Mandarin, they adopt Mandarin as official language.
If it has been the South, it might be Cantonese, Hokkien or Teo Chew.
Anyway, my trip to Guang Dong is quite fruitful. I also learn that the Southern Chinese consider the Northern Chinese bias to the North ad trying to channel major events to the Northern side of China. I noted that the Guang Dong people are quite proud of their achievements with the Exhibition halls, their city highways and stuffs because they managed these without fundings from the Central Government.
My guess is the same for Fujian and Chao Zhou area.
Another thing that I also learn is that even for the North, Shanghai and Beijing are not in good term. They are always fighting for leadership. I used to work in a company where they have people from both Shanghai and Beijing. Although both comes from China, they neve mix.