The very essence of Bitcoin is what will make it last. Bitcoin may not last forever in its actual form, but the fact that it isn't dependent on any government or institution will eventually convince a greater audience and further spread it's use. Physical money is an ancient concept, it's time we start living in the 21st century.
Physical money is an old concept but old does not mean outdated, if people respected physical money and used things of value like we used in the past, like gold and silver, we will not be in the terrible economic situation that the world is going to face in the next decades.