If your premise is correct, that we are not going to re-shore any of the low to mid level manufacturing, then those who are currently having the work done in China will still need to diversify their manufacturing base.
Those yellow bars are in dispute, and recently China has largely confirmed the yellow bars don't exist. The abandonment of the one-child policy came too late and culturally there is pressure to not have kids. Also, see the lop-sided nature of the M-F ratio. Chinese labor cost has skyrocketed relative to the 90s. The main reason why stuff is still being produced their is the cost in building out manufacturing capacity elsewhere. Some companies have, mainly to Vietnam and other SE Asian countries, as well as India, but the Indian .gov isn't as supportive as 80s/90s China was for this sort of thing. Some is coming back to Mexico, but the Mexican workforce is also expensive in relative terms.
See Peter Zeihan's work on this. I don't agree with some of his politics or some of his solutions, but I believe he is good at identifying the problems.