It will be very difficult for a government to adopt Bitcoin as its own currency. Its reasons are obvious, including the fact that Bitcoin can't be regulated as it is decentralized, whereas with fiat, the government can regulate and impose taxes on it.
Banks only interest is the blockchain technology itself, instead of Bitcoin
due to the fact that they could create their own crypto currency in which they could manipulate to their own needs. Just my opinion.
According to me all the part in bold is big wrong. Bitcoin can and is already regulated or partially in to many countries (including important ones such United States or China). In these countries the people can use it, can mine it, can change in other real money (national or not) etc. So your opinion is not true.
Then as for the second part in bold that is totally absurd. Think that the the banks are interested about blockchain because they want to make their digital money have net even the minimum of sense.
First of all, any kind of the commercial cannot make/stamp currencies. Of any kind. Is not allowed by low. Only the Central Banks (or similar Authorities) can do that. The commercial banks use the money as a tool to have their money. To have profit from the use of it. Like every other common business. The difference between a bank and another, whatever can be, business, is only that the banks have as a tool to use to have profit the money itself. While the other businesses have as tool other things in accordance with their area of activity. Nothing else.
Then in world there are thousands and thousand commercial banks. Suggest that every of those can have their coin is to laugh. If true there will be thousands and thousands coins in circulation and all the banks will remain all the time of their existence to convince the other banks to use their coin. Then will happen that there will be accepted all those following the method "I know and use your coin and or if you do the same with mine". So thousand and thousand currencies and no one will use those because will not find portfolio where to put all that kind of money. Then must be changed if some merchants will not accept some and will accept some others.
But the main question to be answered it will be: Why must be this? Who win something? The banks not because will be obligated to use even those other thousand other coins of the other banks and will be a mess. The people less. To complicate. It will be enough to have only one currency by everyone. The national currency and everything is resolved.
