The whole point of advocating for fewer work days is that we are just as productive in fewer hours. That's why overtime doesn't work long-term; you wear out and do less per unit time.
I think that used to be the whole point, somewhere around one hundred years ago. I thought that now the point is, we're doing mostly bullshit jobs anyway, so how about we all agree to work a bit less and have some time to live our lives?
So the reason for working longer hours is to ensure that the Chinese people have to work longer hours (which ensures that Westerners have to work longer hours)?
Seems like a pretty bad prisoner's dilemma - and a pointless exercise if you already accept that China will ultimately win.