Bitcoin is not magic that saves failing economies, so how could it be when it is so volatile that in one day it can lose 50% of its value compared to fiat currencies. El Salvador is a country that renounced its own currency, and Bitcoin is just one more experiment that the current president liked, which does not mean that someone who will succeed him one day will have the same opinion.
Bitcoin market is smaller than stock market and it does now have magical power to fix macro things like global economy or national economy. It is only helpful for people as individuals to find a magic way to get rich or enrich their wealth through investment in Bitcoin for long term.
If a country can add Bitcoin to its national treasury and have good risk management for their treasury, that requires to have some other assets, not only have Bitcoin, they can hold their bitcoins for a long time and see good growth in value. But even so, it does not help to fix a national economic crisis that only can be resolved by government and combined efforts on many aspects in their country.
My opinion is that Bitcoin is not intended to replace fiat currencies, but to be an alternative to them - and no serious country would ever accept something that it cannot control.
Basically governments want to control things as much as possible and they don't suicide by accepting something they can not control but give power to their citizens.