It's still rare to see a country legalize Bitcoin as currency or payment method though. AFAIK most country legalize Bitcoin as investment or property asset, which isn't aligned with Satoshi's goal about Bitcoin as P2P money.
I believe when you say 'legalize BTC as a currency', you mean making it a legal tender. Yeah, right now there is no country where BTC is a legal tender, but that does not stop people from using BTC as p2p money. As long as BTC us not banned in a country, then it can be used as p2p money, you just need to find a merchant who wants to accept it or just anyone who is ready to receive BTC in exchange for something else.