Physical money exist for thousands of years and people used to live with that by generations. That's the reason why people don't understand digital money, money without physical form. How many years will need to people start to use and accept digital money, I don't know.
But now i think that withe the arrival of digital currency the use of fiat currency is decreasing. i am hopeful that very soon all the people of the world will replace fiat currency over digital currency. therefore i think it will be a good decision to save more and more bitcoin as i expect that its value will increase more and more in near future.