China considers all holders of Chinese citizenship, even if given up for a foreign passport, to be Chinese. Additionally, they also consider the children of Chinese nationals born abroad to be Chinese regardless of their legal citizenship.
Yes, I've heard that. It means that citizenship is a relatively useless term. What good does it do for a Chinese person (let's assume Han Chinese) to apply for US citizenship? In the context of the HK demonstrations and the extradition requests, I seriously doubt that logical people in the US would accept that as a rationalization if China demanded the extradition of a Chinese person because he offended or broke some Chinese law.
"China" may claim people of Chinese descent, but that doesn't mean anyone (individual) has to go along with it. That's not even to bring up the situation of Chinese people who marry non-Chinese. Germany had the "blut" (blood) laws years ago. It just meant that German identity and citizenship was constituted by having German blood. Is there such a law in China?
Sure, there are many ethnicities in China. There's even Southern and Northern varieties, not to mention Mongols. At some points, it's hard to tell the difference between Chinese and Russians. Just saying. At any rate, I'm not sure where being Chinese ends.
"A man is rich when he has time and freewill. How he chooses to invest both will determine the return on his investment."