Bitcoin is obviously not a currency at present, not because it is not issued by the government or the central bank, but because it lacks the most fundamental general acceptance of the currency, ie it has not become a currency for most people or for most economic transactions The universal transactional media, which means it does not have a wide range of commercial credit.
That is not the main reason. In a few countries (such as Switzerland and Japan), Bitcoin is accepted as a form of legal tender. So you can't say that it is not recognized by all the governments as currency. The main issue is the high transaction fee and delay.