I'm not going to deny that there's a tremendous amount of scammy bullshit infesting crypto markets right now, but the common idea that cryptocurrency is "backed by nothing" is wrong. If I had to put it simply, crypto is backed by mathematics and Internet redundancy. The mathematics ensures that the ledger for the crypto cannot be forged, and the redundancy ensures that you'd have to destroy the entire Internet and all backups to destroy the ledger.
Frankly I think the biggest problem for cryptos is that people don't generally understand how to "be their own bank" and keep their private keys secure. So they just rely on third parties to do it for them, ignoring the potential for all sorts of fiat shenanigans inherent in trusting said third parties, and next thing you know we're back to the same old problems of fractional lending et al. If that problem doesn't get addressed, then cryptos aren't going to really change anything fundamentally.