How can you day that in the future the bitcoin will be centralise by the government because here all of us know very well that why the bitcoin have the success that is the decentralised , no one except the blockchain team can centralise the bitcoin because people are operating Thier money with the internet access , so any rule will not be applicable over the power of bitcoin and against the government rule of any country .
But still here it is truth that bitcoin will be regulate by most of the country because to give the tax to the country by using the bitcoin is a necessary point because we can't make ownself more profitable only but also needed to give the tax for the government use .
Here some rules are going to br made by my government of India , they said that  they will declare bitcoin as legal way of payment but at every transaction of investment in trading the user will charged by the better tax amount in % , so overall whether we will make profit or loss , only will give tax for it first .
Hope rules should be better so that we can use bitcoin like we are using currently .