Maybe the paper money will change the material that it is made of, at first there were only metal coins, maybe in the future it will be made of plastic but it will never disappear as something "real" and touchable ".
Yeah, the paper money will always be in existence, especially in third world countries, they would prefer to use paper money, as its easy to spend and convenient to use.
why it is for Third world country even all countrys in this world require the paper money, what ever technology come their will be fiat real touchable currency in all country. But the meaning will change like its uses will become very rare.