Survivor Bias at play, the ones do go back, go back. I think the mentality among Chinese research community had changed rapidly, especially in Computer Science field, where China is as practical a choice as US.

The problem with US is for foreign nationals, there is a preset role for us to fit in, while in China, it offers more potentials. I won't say certain it is black and white question at this moment, there is trade-off in between. Living in US is no longer the non-brainer

I'm sure there are lots of Chinese scientists that would never go back, but at the same time there're also plenty of Chinese immigrants (including scientists) actually went back or are considering going back when the time is right, including myself. I think overall more people are considering that as a viable option over the years.

Wouldn't there be an implicit bias towards those who don't want to return? The others made their way back to China.

If you are taking a sample of Chinese scientists 10 years into their career in the US with kids here, then likely true.

My sample based on my circle of Chinese PhD students that have graduated in the last 5 years indicates a more willingness to go back and several have.

You would not be able to work with Chinese scientists that goes back. Sampling issue.