Bitcoin was launched in 2007. It's 10 years and still no country has approved Bitcoin ?? 
and in 2018, 2nd richest man "Warren Buffet" said "bitcoin will end up badly"
Bitcoin hasn't got a good image in some other countries but I think it is wrong saying that no country has approved the use of bitcoin. Because for example in Japan using bitcoin is legal and you can even use cryptocurrencies for payment purposes. There are other countries too like Canada and Germany that has legalized bitcoin. and in 2018, 2nd richest man "Warren Buffet" said "bitcoin will end up badly"