Well, I do not particularly know whether by setting up an alternate mode of payment, Satoshi Nakamoto's goal was to really replace fiat money in its entirety or just exist as a major alternative to it. If it is the former then we still have a very long way to go, but if it is the latter then perhaps we are already functioning more or less. Either way, the full goal is not yet met. As an alternative currency, we are even going down somehow, as people are using Bitcoin as a form of investment.