1. This is a tough question has nobody can tell what is in the future but from the look of things and how crypto is spreading fast,I think digital currency will play a vital role in shaping the way people transact and do business in the future while bank still operates but it will be question of choice from the people.

2. Government can only collect tax if your transaction still goes through the bank and not through p2p method, if you are doing transaction through centralise exchange and have your information taken, there is no way you won't pay tax since the government can easily get hold 9f your info,

3. If people have free access to their funds without any control this will definitely result to corruption and oppression, the wealthy will oppress the poor and nothing would be done, decentralisation has its good side and bad side we shouldn't forget that.