Money paper / Fiat cannot be replaced by Crypto, maybe if we talk about stable coins, it can still be considered, crypto is a fast option that everyone can use when they want to transfer money between countries, without the need for a bank account and it is transparent.
I can see some countries have accepted crypto for payments, but it is still being developed, some crypto platforms are creating many products like EDC machines, and it looks good.
In the future we will see Fiat and crypto being used for payments, without having to replace one of them.