Bitcoin is the test net. The beta product. The proto type. Just how aol was replaced by google, just how Myspace was replaced by Facebook, Bitcoin will be replaced. My bet is Zcash. It solves the problems Bitcoin has. Which are many. Two major issues. Bitcoin is transparent. NO ONE is going to want to store their wealth in a transparent vehicle where anyone can see how much you have and where you have been spending. Two, it is not fungible. One bitcoin does not always equal another bitcoin. Because virgin coins mined today differ from coins mined in say 2013, that may or may have not been used in illegal activities.

Bitcoin is HTTP Zcash is HTTPS