It's not remotely cheap. A long time ago the cheap labor moved from places like China to places like Mexico, which is one of the reasons so many automotive manufacturing plants there - just a rail ride across the border.

Now that hasn't been the case for more than a decade. The cheap labor is in SE Asia and South America.

What China has is decades of process improvement, factories, infrastructure, experience, and a willingness to work. They haven't been the cheapest, by far, for a long while.