Yes, more and more groups are choosing to embrace Bitcoin and abandon fiat currency. This is determined by everyone's basic interests.
I do not know about abandoning fiat though,,, but them moving on to different fiat for sure. The thing about national currency is the whole idea of country/state and identity and all of those things that make 200+ countries feel like they are unique in this world.
That basic interest is stronger than just pure monetary power, collectively,,, this is why Zimbabwe and Venezuela have not abandoned their currencies despite it practically being useless:)