Student visa to H-1B is difficult even for a software engineers. Outside of software engineering, it's much more difficult without a PhD or a high demand masters.
For the vast majority of graduates an H-1B is the only real option and there are only 85k of those given out per year total.
Comparing to? There is no easy legal way into US (if we consider the 'marriage to stay' not legal as we should).
By the way, many other factors are there, from Chinese patriotism to cultural differences, students demographics and American colleges business on foreign students. It's understandable from American perspective to be sure US is the best place on Earth though. But reality is more complicated.
> One 2016 survey of nearly 1,000 Chinese students studying at Purdue University – a large public college in rural Indiana – found that 29 per cent reported developing a more negative attitude toward the US since their arrival.
> Forty-four per cent said their attitude toward China had become more positive since coming to the US.
https://www.scmp.com/magazines/post-magazine/long-reads/arti...
That's the point. There is no easy legal way to become a permanent resident. There are far more Chinese students who want to stay than can, so your evidence doesn't support your claim.
> One 2016 survey of nearly 1,000 Chinese students studying at Purdue University – a large public college in rural Indiana – found that 29 per cent reported developing a more negative attitude toward the US since their arrival.
And a statistically equal amount developed a more positive attitude. I'm not sure what a survey of 1000 Chinese students at a random college is supposed to prove. Students who are willing to travel to the other side of the world are more likely to hold an unrealistically optimistic view of the US before coming here, so it's expected that some percentage of them will have to reconcile fantasy with reality.
> Forty-four per cent said their attitude toward China had become more positive since coming to the US.
Rosy retrospection [1]. People have a tendency to judge the past more positively than the present. If you asked those students the opposite question after living back in China for several years, you'd likely get a similar result with respect to the US.
>It's understandable from American perspective to be sure US is the best place on Earth though.
I can think of several other places that are better in terms of quality-of-life for the average person. China isn't one of them.
Look at per cent of Chinese students staying in US after graduation. It's not that big, considering the student visa to working visa is the easiest legal way into US.