Cryptocurrency, such as Bitcoin, is undoubtedly a meme. If given a choice, one would prefer to possess any of the rare metals, rare earths, or any other elements that can be obtained in sufficient quantities, whether on land or in the ocean. Bitcoin or cryptocurrency is beneficial only to insiders and not to the general public. In essence, they are akin to modern tulips with a cherry on top, and like Tesla in 2030, one should avoid being caught with the bag.
People comment on gold and Bitcoin, but don't realize the same principles apply to US dollars and bonds.
Currencies are a little different, since they are required to pay taxes; and payment of taxes is enforced (to varying degrees) by state violence.
Hence if you believe you will be taxed ("death and taxes" being the only certainties in life, etc.) then the currency associated with that tax has value, in that it avoids imprisonment, etc.
I think you are spot on. The problem comes if SpaceX goes out of fashion, not its fundamentals.