I do not agree with this. Even though Chinese peoples or China may contribute to 1 of the worlds largest buyers we still have many countries who wants bitcoin even people from China are trying to find way to join in crypto currency exchanges or trading.
China is one of the big contributors in the economy of bitcoin but we are too far from becoming dead without them. They have the biggest exchange, they have the most miners and holders. Anyway if they will be out of the league, there will be some other players that will take over if those companies in the China will stop operating. But I doubt it that they will let those companies be out of bitcoin.