Maybe in the developed world country there will be less demand of paper money as they will go to full digital, the world is moving toward digital world if you have notice, we have a lot of inventions or developments to make our life fast and easy.
Hmm when you say developed I see Singapore. But I dont know man. Paper money got a lot of history in it. It will be hard for the government to change it specially for the people also.
THE GOVERNEMNTS WILL NEVER EVER LEAVE THEIR CURRENCY AS IT IS THEIR RESPONSIBILITY AND SIGN OF SUCCESS AND MAINTENANCE THAT THEY SURVIVE THEIR NATIONAL CURRENCY AND TO GIVE IT MORE VALUE, BUT THERE IS A CHANCE THAT MOST PEOPLE START TO SHIFT TOWARDS BITCOIN BECAUSE OF THEIR BENEFITS.