In my opinion if a country fully adopted Bitcoin as its national currency it would definitely be a historic move. The transparency and limited supply could help reduce corruption and inflation but the volatility is a big concern, Day to day prices could be hard to manage and people with no internet or tech skills might struggle. It would push financial systems forward but also expose the country to a lot of risk So yeah it could start a new economic age but only if done with strong infrastructure and education in place
If Bitcoin was the currency of a country, that country would have gone a long way economically. However, as you say a country as a currency, operating Bitcoin will reduce a lot of corruption. But I think corruption can increase a lot if no proper action is taken from the government. Suppose you have one lakh Fiat coins. You can easily transfer through Bitcoin elsewhere. That is why it can be said that a scammer or corruption person can make big transactions through Bitcoin. But yes it has many good aspects such as using Bitcoin of all will increase a lot of resources. And citizens have to have a high rate of education so that no complications are encountered.