Its actually great that the amount of people and not just the Bitcoin within countries is growing internationally but at the same time, as time passes by, countries will continue to adopt Cryptocurrencies into their local businesses. It will still also be a great technology advancement since financial technology would start jumping in into this kind of system and from that point, advancement would just continue to into a better lifestyle for everyone.
in other words in the future bitcoin will not be able to rule the world because it would be against economic law, if the world currency can be controlled by bitcoin then there must be one country that is able to formalize this digital currency so that it becomes centered in one country, but we are of course already know that no country can regulate Bitcoin. even if that happened the characteristics of each country would be lost because the local currency would be worthless