Again, I am not a crypto guy, but the valuation of equities, fixed income, real estate, and other assets are ALL based on the expectations. A company's stock is valued off the expectation future earnings and revenues and a variety of other factors, and it can drop to zero in a default or bankruptcy or liquidation scenario. In addition, helicopter drops of money impact equity valuations, too, as does the rush of new investors to that company's stock who bid up the price.
I totally get that crypto isn't backed by hard assets, and that's a legitimate concern IMHO.
It’s literally created out of thin air, infinitely, using computer cycles, which get cheaper to produce by the day. So there’s no limit on how much there can be, and the raw source is more available all the time. It’s literally the worst investment I can think of, only held up by speculators, who will eventually flee when these truths are finally accepted.