It's not likely consumer taste shifts; it's deeply embeded in Chinese culture that men need wealth (real estate primarily) and a dowry to a woman's family in order to propose marriage. Combined with far fewer women than men due to China's one child policy [1], it's created two classes of men: those who will continue to attempt to amass wealth to woo a mate, and those who have given up or have looked outside of China for a companion ("lost men"). The wrinkle is that more Chinese women are also opting out of marriage entirely, further increasing competitive forces.
It is hard to ignore cultural norms when you operate in a culture, and these norms are creating inelastic demand for housing. The prospect of being alone for the rest of your life is a powerful motivator.
[1] https://www.washingtonpost.com/graphics/2018/world/too-many-...