The future of paper money is safe as I don't see any threat to it from bitcoins as paper money is widely used and accepted and that is not the case with bitcoins at a moment and even in future if bitcoin becomes more popular still there will be many bunch of people who will prefer to use paper money and not bitcoins.
The rapid growth of the technology is so fast that we didn't even see it coming, it's been a while when me and my friends are just communicating through text, but now I rarely see someone using text message these days. All are almost chats and Messengers. Maybe you are not seeing it now but the time will come where digital money will reign the financial world.
Cards, smartphones, chips or even scanned images to buy or sell goods or to pay for bills will make it's mark before 2030.
Papers are made from woods so we must preserve that, it will just fade due to degradation so must change to something long term. We must make use of our spectrum space.
Digital world must provide an digital money and thinkers and users. Traditional way of payment will fade.