I have been working with China since 1981 and made a few visits in that time.
No country has changed so much in that time and now , like in many oither indutries, it is a leader in the production of chemicals and ingredients. For instance Vitamin C is made predominantly in China with only one site outside , in Scotland, where DSM still produce.
China produces very good quality products although they do have a few hiccups where the Western Customers require non Chinese sources as a hedge against quality. However in many cases like vitamins, there are no real alternatives.
Currently the biggest problems in China is the environment and air quality. The Chinese Government has the power to quickly close factories that do not conform to ideas about the environment. This can lead to acute shortages of products. In 2016 the government closed many factories to improve air quality for visiting dignitaries. This also happened when China hosted the Olympics in 2008.