Currently, there are many usd-based stablecoins such as, usdt, busd, usdc and maybe many others. To be honest, I used to think that crypto would completely eliminate the usd's dominance of the world economy but I was wrong, it turns out that usd is now evolving to crypto (stablecoins). What do you think, whether in the future bitcoin or other crypto can replace the role of currency in each country and leave fiat currencies such as usd, euro, yuan and others.
It is better you do not get your hopes too high about this happening in the future, while many of those that came early to the market and adopted bitcoin have had a similar dream the truth is that was not a goal of satoshi, satoshi created bitcoin in order to help you to truly own your money and become your own bank by not relying on a third party to approve your payment, satoshi succeed since you can already do that and the dead of fiat currencies is not really needed.
If you are still thinking that fiat will be eliminated soon and that crypto will be a global currency, that is still too far from reality. They might coexist in the future, as well as crypto can be integrated in bank's transactions, but crypto will never replace fiat. People might be amaze thinking how bitcoin can be a good currency but when it comes bitcoin as the only legal tender in different countries, big adjustments will definitely arise. So let's just be contented having them both. I guess it will even create a harmonious relation between fiat and crypto and the people will definitely love using them both.