This article is actually nonsense. Shenzen may well be the electronics capital of the world. However, Shenzen is completely willing to sell parts to any corner of the earth. Apple makes phones in China because labor is cheaper in China and corporate bonuses are more important than … (fill in the blanks as you see fit). The issue is CEO paydays (9 figures and more), not the merits of Shenzen as a technology hub.
Here are some approximate numbers. Foxconn employs roughly 400,000 workers on behalf of Apple. Pay for Chinese workers might be $50K (at least, one you include benefits) less than U.S. pay. That’s $20 billion a year.
Apple makes phones in China because Apple wants $20 billion (at least) more in profits.