:)Bitcoin was launched in 2007. It's 12 years and still no country has approved Bitcoin ?? Huh
and in 2018, 2nd richest man "Warren Buffet" said "bitcoin will end up badly"

Because every country already has a currency.
And i've heard,Japan Korea Russia Legalize bitcoin.
But I am very sure, someday more than 100 countries will Legalize bitcoin
What do you say?
Cryptocurrency is unlikely to replace fiat money. The price of Bitcoin can be listed and calculated because of fiat money (btc-usd or etc)
there are already 5 countries that accept Bitcoin, Swiss, America, Malta, Singapore, Japan.