Why do you assume that based on his comment? My assumption was the opposite, though it was still a slightly unexpected thing to mention. It seems to me that someone who hadn't been to Shanghai and Beijing or who had just been there briefly might just assume that everything was very inexpensive.
If he hasn't been to an Asian city, that is a perceptive comment. Many people from the center of Beijing and Shanghai have had to move out to the suburbs due to relocation programs in which they are badly compensated for their high-value properties in the center. Prices are extremely high for the original inhabitants of Beijing and Shanghai. Obviously, there are countless exceptions, but inflation is extremely high, and many people have had to move out of the city centers. This was an interesting aspect of urban development to mention, but it is a theme nonetheless. There are also huge waves of migration into Shanghai and Beijing, but that doesn't change the fact that people are essentially being priced out of the city centers. Well, to be honest, I don't know the situation in Shanghai very well.