From my point of view, no country will accept BTC as a formal currency at present or next time. The reason is that the government fears cryptocurrency and especially Bitcoin will affect the development of the national economy. If a country does not accept the BTC as its official currency, the country has inadvertently made its currency insignificant compared to the BTC because it is now at a very high exchange rate, even higher than gold. So I think no country will accept the BTC at this time as the official currency.