i think bitcoin has surely played a pivotal role to get Blockchain going and putting it where it is today. But I firmly believe that even if Bitcoin fails in future, the blockchain technology will prevail. Hundreds of interesting applications being launched on Blockchain tech and some of them will get traction for sure. Even without bitcoin, blockchain still can run and I believe it will survive. The blockchain may not be known that much without bitcoin but because there are altcoins it may, depending on how this coins are promoted or used