I doubt that cryptocurrency give such freedom. The government will not allow it, it is not profitable. They will be a big loss

I hope so but no one can really tell. Crypto will stay forever but mass adoption is the main challenge that we will face. with all the regulations and laws from different parts of the world. it will take a while.

It is said that bitcoin will destroy the fiat system but i believe that if this happens the world will change completly because banks and a lot of things will go out of market.

the correct answer is Maybe.

you can't say at this point what will happen in the future. but as far as speculation goes i think it can be used by many people but bitcoin will not replace fiat.
I do agree that a lot and still more and more people will be using bitcoin in many of their daily transactions wherein bitcoin payment are accepted especially the youth and the professionals. The spread of bitcoin is really amazing and people just love its convenience. However, it cannot delete the existence and the need for fiat since some people like the oldies will have a hard time using smart phones and prefers the traditional fiat just like here in my home country.

It is very necessary because time goes on and people will learn more all about cryptocurrency. But no one can predict if bitcoin will come up unti 2022. In 2022 it maybe called the cashless time.