>An anecdote: none of them want to immigrate (at least to US)

I think your sample is skewed. Chinese people from all social classes are immigrating to the US at record rates. The US gets about 25% of all Chinese emigrants each year, a number that's been growing not decreasing. China recently overtook Mexico as the top source for new immigrants in the US.

Look at the number of Chinese students, the number of H-1Bs, and the number of Chinese green card applications for evidence of middle class highly educated immigration.

For less educated immigration, visit any Chinese restaurant in any backwater town in the country. You'll find that the front of house is staffed by an endless supply of new immigrants.