No one actually knows, if bitcoin will be gone, there are still other altcons. Take note that bitcoin and other altcoins has their own use case and purpose. Another coin might even pop-up which has the same purpose or even surpass bitcoin's convenience and use case. I am sure that crypto currency is here to stay since we are already in an era where people are dependent in technology, and cryptocurrency is the next best thing in terms of technology, safety, and fund security.