Do you think I just fell off a yùtóu wagon?
I've been to China numerous times, have many friends from and in China, am married to a Chinese, and you are so full of it I'm looking for my waders.
This is *all* about maintaining order, under control of the CCP, by blocking (or at least slowing down) the ingress of as many "disruptive" ideas as possible.
Meanwhile, within China, it's common knowledge that many of the country's current social ills stem from the Cultural Revolution and its attempts at erasing this 5000 years of history of which you speak as though it were really a presence. It's common knowledge within the CCP as well--I know this because I've discussed it with Party members.
So please spare us the "preservation of our culture" spiel--it doesn't wash.