Bitcoin will soon replace the Fiat and all the paper currency which is currently being used. At the moment this seems a bit unrealistic thing to be happen but then no one thought 20 years ago there could be any digital currency. Things are happening rapidly and many companies are integrated bitcoins into their business. Slowly we are moving towards a totally digital world.
I think the term totally digital is going to be more hurtful to the world than be better than what it is today. Remember that the sole energy source is still from the environment and (god forbid) nuclear, and once we get enough power to run such devices worldwide it will be tough be remain eco-friendly.
Not being skeptical but I also hope that bitcoin will take over fiat in maybe another decade or so but I cant say about the consequences for sure. People have never really accepted bitcoin as something usable in the first place due to high transaction fees and heavy network congestion - in some cases where paper bills are much more friendlier.
Still considering bitcoin will prevail in future but the acceptance of bitcoin also needs to grow - which is growing at a slow rate at present.