The existing banking system is not so bad. If from the side of citizens it looks quite tough, then from the side of legal entities (enterprises of various forms of ownership), this is a convenient form of financial relations by the fact that banks confirm any payments with all participants, the purpose of the payment, and other details. This information is needed for tax authorities and auditing. Cryptocurrency cannot provide such transparency of activity and therefore is not suitable for legal entities.
Cryptocurrency is very suitable for individuals. However, transactions between individuals will be few. But how will citizens purchase various goods and services from enterprises, this has yet to be clarified and improved.
These forms of financial relations can exist only in parallel with each other.