How is that any different from Fiat money? Or anything for that matter. It holds no real value beyond the paper it is printed on. It is valuable because we all agree as a society to give it value.
Cryptocurrencies lack sovereignty and don’t have an alternative source of baseline demand, which is why they’re volatile on a level normally associated with collapsing states — especially if they’re like Bitcoin where the deflationary model encourages everyone not to spend. When anyone can easily set up a functional equivalent, there isn’t much to anchor the valuation. This is why people created things like NFTs to give others a reason to buy their tokens rather than someone else’s but that’s not especially stable until those NFTs are accompanied by legal contracts conveying tangible value.
I personally feel that we are still in the very early stages of this tech and I think it will continue to grow.