AFAIK people who live in China mainland can buy Bitcoin in Hong Kong, so it's not really a new thing to see China mainland's citizen can own Bitcoin. As long as the ETFs or Bitcoin acceptance was happen on Hong Kong instead of China mainland, I don't see anything bullish from this news.
People who live in China mainland that own Bitcoin or ETFs might have a problem since their banks restrict funds from Bitcoin.
If what you think is true, then the HK spot BTC ETF would have already recorded massive inflows of money from mainland China, and no one actually mentions it, given that the amount of money they have in HK is almost negligible compared to the US. Nothing can surprise me when it comes to China, but I think that Bitcoin has finished its story there, at least for a long time.
A lot of people are banking on wealthy Chinese locals, but, officially, you cannot buy this ETF if you're a mainland Chinese investor, said Eric Balchunas, a senior ETF analyst at Bloomberg. Thats because it must be listed on something called the Stock Connect, which allows Chinese citizens to invest in certain Hong Kong ETFs, and vice versa. This will never be available there, says Balchunas.