I don't believe this in a majority of my brain, but the thought has crossed my mind that China's draconian COVID response is to hide their real estate collapse and other macroeconomic problems.
Their COVID response is mainly about control. for a time it was also about nationalism (look at how many people are dying in the west). At this point it’s control and a little bit of Xi not wanting to change the policy until after he has secured another term.
But that can also be true. Global economic stuff is out of China's control so how better to hide it than with something where they are in control?