I think this could be changed but for now it is very difficult to achieve it, if crypto replaces fiat, of course there will be many negative and positive impacts, such as payment transactions will be fast, and the shortcomings as well as when the transaction is disrupted will disrupt the process
It is clear that with crypto payments will be faster and more measurable and process faster. but there is also a problem with crypto replacing fiat, because there are still many countries that have not been able to accept crypto transactions as legitimate transactions recognized as legitimate payments by the state.
you're right, in terms of transactions, of course crypto is very fast. however, the thing to consider is that fiat is used for offline transactions, and crypto is used for online transactions. moreover crypto has a volatile, or unstable price. of course there is a lot to think about in this matter.