Here's the problem with your reasoning: The likelihood of Bitcoin becoming world's major currency is slim enough to make me (and my Lizard Overlords) laugh. If it does become a threat to the status quo, it will be banned--already talk in Russia of criminalizing it. It won't vanish, but it certainly won't thrive.
"The
primary purpose of evil people is to instill helplessness in the morally energetic." --Stefan Molyneux