bitcoin is not going to replace money for today that's my opinion, because many do not know about bitcoin so money is still in need, and also money is the identity of a country
You are absolutely right in this regard but things are not like this anymore. Yes for current scenario bitcoin is not that much available at every level of population but we are talking about the future. And surely, believe me in future, there will be no paper money because the whole system would be changed into digital world and we will be seeing bitcoins everywhere.