Integration isn’t the same as substitution, it means I can pay a dev living in Indonesia in eth and they can deposit it to their bank without having to go through a third party, because it’s a hell of a lot faster, safer and easier than trying to set up an international wire transfer between banks who don’t speak the same language.
Furthermore, if cryptocurrency helps a population regain control of their finances in a failing economy, how is that a bad thing?
The whole first world-third world designation thing is about as outdated at your information.