I think he said that Bitcoin is controlled by the Chinese people is because that the majority of Bitcoin Mining giants are from China, In my conclusion, decentralized currencies like Bitcoin can be controlled by a group of people if they have a huge amount of this and they are hoarding it. For example, in my country, there are a lot of basic goods hoarders, what they do is they hoard a certain kind of goods either it's a vegetable or anything else and with this technique they tend to increase its value by up to 50% to 100% and in my own opinion if this thing happens to Bitcoin the price might increase too but still too risky.


(PS: hoarding goods is illegal)