That feels like a very different thing. Those interns come out of college with double the salary of their peers and insanely good career prospects. They often come with strong backgrounds and from prestigious schools - they can do almost anything they want.
They can work in retail or commercial banking instead if they want better hours.
I actually don't know, but my impression is that they were often at tech companies where the salary trajectory is a lot less steep, and also there were far fewer alternatives with a good work life balance. This always is framed as a pervasive cultural issue in the media I consume. Could be totally wrong though.
Just Google online and you'd see that the average salary for a software engineer in China is pretty high and has pretty good long term career perspective (+ stock and bonuses)
They can work in retail or commercial banking instead if they want better hours.