That is not what has happened over there, people in El Salvador are not using BTC as much as you think, and so many of them who downloaded the Chivo Wallet probably did so because of the $30 bonus they were to earn. Take note that no country can be 'decentralized', i don't know how you think that can happen, there has to be a government that is the central authority in charge.
El Salvador is a small, poor and insecure country, and they are struggling economically and are in serious debt, i don't know how they are going to come out of all this, but it is surely not through BTC as some people think.