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.
I also believe that bitcoin will be used in 2022 by everyone but the other part of statement is not correct, as banks can not go out of market, they are the most important tier of the economy of a country. The banks are the issuer of loans to the people of a country and they help the economy to grow they create money without actually increasing the money supply by the money of depositors, so they have a very important role in the market and will be present for a long long time.
I simply agree with you in a way. Although almost everyone in 2022 is something no one can really tell since it is closer than anyone can imagine, but there could be a possibility of slightly all learned people and those who have access to the internet.
There is a huge population of some people in the world today still lagging behind with advancement in technology and those set of people cannot be ruled out. However, what I agree mostly is the part that banks cannot be sidelined with the presence of cryptocurrency.
Fiats are controllable and government will never give that up for anything. Even with the existence of cryptocurrency, there will be so many people who will rely solely on the usage of fiat and with that, they will keep being in operation.