To be sure they do get some support (launch site logistics and handling, test benches etc) but until recently China's space startups act more as ways of offloading risk for R&D in the launch sector without being given huge responsibility (so far), as it still conducts all of its important launches under its state-controlled space programs.
You'd be surprised how much the government leave these startups to their own devices. It's quite unlike NASA where they are integral technical partners of SpaceX, helping them develop Falcon and Dragon, especially under-the-hood tech, and are still assisting them with a ton of CFD, material science and sims work for their other projects.
The silver lining is what would be considered proprietary information in the US (IP developed by one co is certainly not given to another) is culturally irrelevant over there. Information is shared rather freely across China’s aerospace sector. Once a few of these companies demonstrate their reliability the state will get more hands-on and give them more responsibilities.
