I cannot rule out the possibility of paper money to dissappear but it will take more than a century. Most digital currencies including Bitcoin are still in the middle stage and therefore cannot make paper money to dissappear so quickly.
In order for paper money to completely disappear, it is necessary that the digital currency works smoothly anywhere in the world, it is necessary to develop further in this direction.
i do not think that it is such an easy job that paper money will disappear completely, as in present time less than one percent people of the world are using bitcoin, i think it will take a long long time and even then people will be using both the option. to me i think it will take decades when all the peoples of the world will be using bitcoin in every corner of the world. in fact still there are some countries and modern cities where people are already using bitcoin for payment method as well as for so many other purposes.