If all countries can accepted crypto currencies in there various countries, as a means of payment and as a means of online exchanges, such as money is, money is anything use as a means of exchange and general acceptable. With the means I think all cryptocurrencies (bitcoin) will definitely go round the world, and will be use as a means of exchange. I will be so grateful to the creation of crypto currencies. This will also help our future generation, Remember something when we do international transfer across the countries, it may take a while to get the money to your local bank account, but with cryptocurrency you can get instant reflection if bitcoin etc is transfer to wallet,And you can make use of your coin (bitcoin ETC).
Bitcoin is still a highly volatile asset and hence not much suitable as a medium of exchange, though it's really good as a store of value. Stablecoins can serve as a medium of exchange, including international transfers, as they can be easily pegged to USD. I believe that in the future, some digital assets (either stablecoins or any other crypto assets, not necessarily Bitcoin) will be used for global transfers and will successfully compete with traditional currency.