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.
Bitcoin will not destroy the fiat system because first it is decentralized digital currency which is free from govenment or even on any single authority. Banks also did not allow it,maybe they can create anothen coin and make it centralized but not the bitcoin. Government can implement tax and regulation but it is not easy because bitcoin transactions are anonymous. Decentralized and anonymity are the best nature of bitcoin and because of this more people contunue to trust and patronize it. The demand getting bigger and bigger as the years had past and i believe during 2022 almost everyone will use bitcoin even those on remote areas as long as there is an internet connection.