Yes, this is money of a new generation. Of course, they will not become the main single currency in all countries, but they will be a wonderful additional currency.
You must be dreaming, it's impossible for bitcoin or any crypto currency to become the main currency for all countries.
As long as there are people who govern this world, the centralized world will prevail over the decentralized.
Why not? like what others said here, we cannot predict what will happen tomorrow and we also not handle the mind of others for what they are thinking of. ANd there are impossible things which is in the long run became possible, Which means if the government wants bitcoin to become centralize that's won't really be happen but bitcoin can make government to adopt it and can declare it in the future to make it their own currency little by little.
bitcoin actually can be whatever people want ,
when you use it to purchase something then bitcoin as a money ,
when people use bitcoin as something like commodity to trade then it could be like that ,
when people believe future of bitcoin bright enough to store your value in long term, then bitcoin as an investment ,
it's decentralized forever i guess nothing can changed into centralized.