“when some 330 million smartphones are sold in Chinacevr5y year”
Sold to the emerging Chinese middle class who can afford to buy them because Western companies are paying them more than they used to earn farming. Western companies leave and they are back to farming and no smart phones.
That scenario is no longer the case.
Most of the smartphones sold in China are manufactured by Chinese companies like Xaomi, Oppo, Viva etc etc.