This is funny statement which is totally not true. He is just trying to destroy bitcoin and for ripple to gain more investors which will not happen. It is true that china have the most share of bitcoins hash power but even you sum all the share of those miners from china they will not be able to get 51% to be able to execute an attack. One thing is for sure no one can control bitcoin but ripple is controlled by the company who created it and remember that they kept huge supply to control the circulation of this cryptocurrency.