The article claims the BYD F3 costs half the price of the Corolla. Despite its recent recall problems, Toyota has a highly efficient inventory system, and I highly doubt that 50% of the cost of the Corolla is profit.
Is BYD's car really equivalent to a Corolla? What exactly are they copying then?
Part of the cost is due to design engineering, not just manufacturing. Since they are just copying the design, they can save a quite a bit.
The Japanese also had a reputation as 'skillful mimics' in the US during the 1950s and 60s. It wasn't long before they could outdo their mentor.