I'm not comparing it to US anything, I'm comparing it to other cost components like raw materials and parts, whose prices are often global.

The point is that transportation within China isn't a dominant factor in industrial cost or efficiency. So the idea that major manufacturing cities are laid out like giant assembly lines isn't nearly as important as OP suggests.

China still has many advantages over the US in manufacturing. I just don't think this is a major one, even if there's a grain of truth to it.