Many people do not believe what Chinese government can bring to the global economies. I have been many times in controversial debates with them. Personally, I believe that China can impact the global economy very much as it is a huge influencer. The ratings that they release is good information for accomplishing better results for businesses that are in fond of these ratings.
Or maybe all they want is to make more profit, so they are promoting a coin that's different from bitcoin in order for people to buy it and grow its price. You never know what's in their mind so all we can do is make predictions about why are they rating cryptocurrencies this way.