Yes agree, the future of the financial world is cryptocurrency, we are not too late to follow, I'm sure 20 years longer all transactions will use the cryptocurrency.
I think it is impossible for all transactions to use cryptocurrency, this is because until now cryptocurrency is not in physical form so the use of cash is still a lot.
It may not be possible for that to happen all over the world, but it is possible that to happen in developed countries since most of the transactions are in electronic form already, in fact, it is becoming rarer to pay with cash, now most people use credit cards to pay their bills.