I do not feel that robol was being racist at all. A very simplistic view indeed.
It is common knowledge that the emerging traveller from China is in need of some training in regards to acceptable behaviour in an international setting (including on board their own aircraft).
This is proven by the fact the the Chinese government (only this week) released a 64 page booklet on ettiquette, manners and general courtesy for their citizens wishing to travel overseas. Topics inclusded
-How to queue in an orderly manner
-No to spit the contents of your chest onto the ground
Plus much more.
And yes, i have flown China Southern from CAN-LAX earlier this year. The ongoing commotion within the cabin for the entire flight was quite horrendous indeed with no concern for other travellers. IFE was patchy (probably more than 1/2 not working), and service was robotic. However seats were comfortable, and for the price paid (3/4 the cost of using another carrier), I still do not know if i would retry them.