Firstly i introduced with crypto world by one of my Facebook friends. That time it was for me only a place to make money. But the more i got involved in this world i realized its a reveluctionary tech which can change the world financial system completly. I can not say its future but i can predicted that it can be an alternative of paper money.
You're right fiat money or paper money could both co exist with btc and other cryptocurrency. We have almost the same situation on how I get into cryptocurrency. I have a friend in facebook who introduced me how btc work and how i can able to earn from it. I didn't believe him at first but I found my way in with my own research.
they can exist together but the proportions will constantly change. Now fiat money is winning because the technological development of cryptocurrencies is very slow. starting from 2021, everything will begin to change and I think that this will happen very quickly. we will need another 5-7 years for the cryptocurrency to be used more often than fiat currencies