Seems like you really are focusing on money when you say that you don't need the governments and banks anymore because of blockchains. You must be forgotten why is the government here? They are working in different aspects and problems of your country so you are deeply mistaken when you say that you don't need banks and governments anymore.
If we only talk about the digital currency,i say it yes we not need the banks and the government for all. But don't you think government and banks are important in real world because if there is no government I don't think that one country will have a unity or have a good. We need the government to rule to make good are country and about the banks it is important because we can't say that the software wallet are realy indestructible because there are many hackers too
Yes I totally agree with you. And if the government seen cryptos as a threat then they will make a move and ban it as soon as possible. And I don't think FIAT will be replaced by crypto currencies although there is a possibility but I think government wouldn't allow it.