It really means that all the private ownership in China is conditional and heavily restricted by something that transcends it. In particular, China is taking control over the cryptocurrency business in that country. The government can do many things with it. It can really do anything. And it can do some relatively interesting things, too.
It's rather likely that the people who were running the exchanges and/or the mining farms in China will be punished. Well, those who won't be punished either by the death penalty or by life in prison will have to be very thankful. (The cryptocurrency exchange bosses have already been given a travel ban.) And the government may just liquidate this "evil portion of the grey economy" where people got very rich for no good reasons.
The government in China may choose to act as a bull in china [pun intended]. Such a bull in china would act as a Bitcoin bear, not bull, however [another pun intended, I am on a roll]. The drop of the price from the record high $5,000 to $3,600 today could have been caused mainly by China – but China may cause much more brutal collapses in coming weeks. The rest of the Bitcoin holders may recover and switch to the thinking that "they are paying with a future currency that works outside China". And that divorce will be the end of the story.
But China can do something else than this destruction, something that is more creative. It may just nationalize the companies, especially the mining farms which are interesting because they come with the power. It's possible that this process is already underway. From this perspective, you should be able to conclude that 65% of the Bitcoin mining capacity is controlled by the government of China.
Well, that makes a difference. These miners – that will be centrally controlled – may change the rules of the Bitcoin. Again, any such change could be just "destruction", resembling what Daesh did to various old structures in the Middle East. However, the change of the rules could be much more creative and "potentially beneficial" for China.