The whole reason Apple let a Chinese company manage their customers' data is because the Chinese government changed the law to forbid them operate those kind of cloud services for Chinese customers themselves, the same reason other companies like Amazon have to let Chinese companies run their version of AWS:
https://www.reuters.com/article/us-china-apple-icloud-insigh..."In a statement, Apple said it had to comply with recently introduced Chinese laws that require cloud services offered to Chinese citizens be operated by Chinese companies and that the data be stored in China. It said that while the company’s values don’t change in different parts of the world, it is subject to each country’s laws."
Also note how the Chinese government effectively set up and runs this company, so the government more or less forced Apple to give their Chinese operations to them.