Might there be some confounding factors. Perhaps having a stable job at a factory, even if it's FoxConn, is better morale than being a perpetually marginalized

Might there be some confounding factors. Perhaps having a stable job at a factory, even if it's FoxConn, is better morale than being a perpetually marginalized migrant worker that's tossed from abusive employer to abusive employer since you left your family in the countryside to find your fortune, despite lacking credentials, in beautiful Shanghai? Actually the few I met seemed surprisingly chipper. That must not be it.