This is probably due to high real estate prices (around 1M RMB in large cities like Beijing and Shanghai for a decent apartment that can get you a girl to marry you, yet you don't really "own" the property even if you buy it. Technically the state still owns your apartment and you were just paying for "usage fee" because that's how communism/socialism works. In comparison, newly college graduates earns around 6k RMB/mo); broken health care system (probably worse than the U.S, since most of the Chinese family are relying on their only child to provide health care money when they grow older); harsh job market (simply too many people for not so many jobs, so the wage becomes low); and plus, a dim future for all of the lower income families or family without connections.
Yes you can argue that there's so many opportunities in China, but somehow we voted with our feet: everyone who has a means to leave left. Most of the famous Chinese actors are now foreign citizens or at least with a green card alike. For average families, they send their kids overseas for school. That's why you see so many Chinese students overseas, doing boring PhD degrees if they are poor or enroll as an undergrad if their family could afford. For their families, getting their kids to an overseas school is like taking the first step to a much more promising future.