Is China really controlling Bitcoin?
For you able to know, China is not controlling Bitcoin, it maybe they have plan to do it but they can't. Why they can't? This may know most of the community here which is the decentralization this features of bitcoin is one of the powerful thing it has that's why many are trying but always fail to do so.

Is Bitcoin really controllable?
Bitcoin is controllable only by You, It can't be control by anyone unless you give your password or private key.
Always remember that  Bitcoin is not regulated industry it is unregulated concepts.