Bitcoin is not just software. Bitcoin happens to be a protocol, and as it becomes more popular and entrenched as the de facto cryptocurrency, it will be near impossible to replace it with a new cryptocurrency. It's called the network effect. If people can't be bothered to try a different social network than Facebook, they sure as heck are not going to be bothered to switch to a new cryptocurrency (and certainly not on a whim).

Browsers actually include gopher still don't they? Wasn't one of the selling points of the early browsers that they did all the usual stuff like gopher and ftp plus also had this newfangled web thing too? Did they ever drop gopher support?

-MarkM-