This is because they can't find jobs abroad and can't even speak a foreign language properly after spending their undergrad years in a Chinese international student bubble.
Quoting China Daily is irrelevant because it's a propaganda mouthpiece of the CCP.
My understanding was that increasingly, overseas students are returning to China? (known as "hai gui", sea turtles)
See e.g. http://www.chinadaily.com.cn/china/2016-03/18/content_239314...