I think the article and associated articles just don't haven't had much time invested into developing them. For example, the articles for the regions in China

I think the article and associated articles just don't haven't had much time invested into developing them. For example, the articles for the regions in China don't mention that they're closed cities. And for the current closed cities in Russia, their articles just say that they're closed in the first sentence and don't reference it again. I think there's a lot of scope to develop the article and associated pages with more information.