Xi's China is closing to the world. And it isn't just about borders
https://edition.cnn.com/2021/11/14/china/china-border-closure-inward-turn-dst-intl-hnk/index.html
Xi would think that international interaction will be risk of Great Firewall. Even if censorship on the internet is effective, those who interact with international friends or acquaintances will learn the things Chinese government wants to conceal.
So, border closure would be kept for the time being.
