I don't think there's an easy answer here tbh, like yes they're taking advantage of a healthcare system without providing a lot in return for China, but at the same time it's still good that people are getting treated. Also, I feel that this helps the westerners see the Chinese system's achievements firsthand, which creates a more favorable picture of socialism in the long run, so it's worth it imo. That being said, we don't know the numbers, so no easy definitive answer.