Earlier quoted context omitted.
Access to people that write good english can be very hard to get in China, so that is probably not a good indicator of anything in this case.
Unless the Great Firewall also blocks websites offering proofreading services, I'm not sure if that's a valid excuse.
On the flip side, I often see equally poor translations of English documents to Chinese. I'm not sure if we have a similar firewall preventing access to proofreading services.