Interesting food for thought, good question. Things have value because people say they do. Things are worth $X because someone is willing to pay $X for it.. the same is true for Bitcoin (price manipulation aside). However, I don't think you should be so hasty to go "all-in" on Bitcoin and think that nothing could or will ever surpass it. Bitcoin sparked the digital cryptocurrency interest and attention worldwide, and has remained arguably king ever since, but that doesn't mean it can never or will never be surpassed. Time will tell. In the meantime, take your own risks of course, and consider the possibility of "backing multiple horses", perhaps? That way if Bitcoin gets surpassed in the near-to-mid future, great, you accounted for the possibility; if not, great, you have enough Bitcoin to be satisfied with that decision as well.