He is presumably a very old Chinese man living overseas who has some of the same wonderful fantasies about Japan that his peers have. He relates some irrelevant factors to the development of Japan. If Japan's GDP per capita is lower than Korea's this year, he will immediately make up a set of...
All of his opinions are basically based on imagination. Don't expect him to have any authoritative sources, there has never been any information that proves the PLAAF doesn't need the J-3X or J21.