This might be one of those lost in translation misunderstandings right?
I think a majority of the factory workers 10 or 20 years ago were what's called 农民工 in China.
Which translates to farm worker or peasant worker. They had rural hukous (registration) but worked in the urban areas.
The term is pretty widely used:
https://www.tandfonline.com/doi/full/10.1080/02723638.2023.2278959
https://research.nus.edu.sg/eai/wp-content/uploads/sites/2/2024/09/EAIBB-No.-1785-Chinas-peasant-workers_post-COVID-trends-synopsis_exsum-1.pdf
Today, most Chinese would be considered middle class though but there are still hundreds of millions that can be considered peasant workers.
I think in the West, the word peasant has somewhat negative connotations..
I think there's a mix. There's still considerable low-value production but labour costs are multiples that of SE Asia but that's offset by supply chain and infrastructure advantages. But China also has the world's largest base of advanced and automated manufacturing. This is the kind of manufacturing that you want to onshore from China.. But other than tariffs, what else can do you do?