This has a lot to do with Hainan's economy. Hainan is in a period of development, with agriculture and tourism as the mainstay. The economic foundation is not very rich, but it is definitely a good place to choose to live, with very good air and good greening.
Hainan's civil servants feel ok to build fund-raising houses in recent years. My classmate Haikou was assigned a house just two years after he joined the civil service.
If so, it's still good.