Dealing without knowledge is dangerous. It is not a dangerous in countries but Bitcoin is decentralised cryptocurrency so government should not control the coins .This is purely transparent in all the peoples so many banks are affected in the country. It is the main reason to avoiding the Cryptocurrency legalisation. But some countries are looking to advance technology so they all are agree with Cryptocurrency because many peoples are supporting to crypto investment. Fiat is backed up by the government and people use it for all purposes, so it is quite safe. Cryptocurrencies are volatile and in a way there's some danger of people losing their money with them, which is why they get banned .