In fact, outsourcing was only possible because of the various industrial plans that China had put in place in the 1960s, 1970s, and 1980s, all of which prioritised building equivalent capacity to what existed in the West and the USSR.
Moreover, China was destroying its environment in the 1950s already, long before it even allowed real trade with the West.
Let's treat countries as responsible actors in their own right, not as mere non-independent reactors to Western actions.