The outsourcing of manufacturing was largely influenced by the externality of environmental pollution. People wanted to live in clean habitats. We had rivers on fire for weeks, extinction of species, and horrible pollution causing cancer and birth defects. Giving "the commies" the dirty, dangerous jobs, and moving everyone up into middle management and white collar knowledge work was seen as an evolution of the economy.
The political move to put all of that death and destruction onto China, where environmental regulation is willfully ignored in the interest of economics, was a smart move on their end.
We lost so much intellectual knowledge and other "tribal" technology in these processes to this outsourcing, which is unfortunate. We're almost having to rebuild our manufacturing from first principles, which may not be a bad thing.
You don't have to completely abolish manufacturing to clean up pollution better.
Clean Air Act was passed in 1963. the Clean Water Act was passed in 1972. The China Shock began in 2000 after PNTR.
Avoiding environmental regulation was one reason to move factories to China, avoiding unions and high wages was another.
But the local communities weren't demanding that their factories be moved overseas so they could have a clean if impoverished towns. Your entire causality is completely backwards.