HN can't think past price goes up/down and see that a lot of crypto is a valuable resource that you can use as collateral and borrow against it without having to go to a bank and beg for permission.
I can take crypto (and I'm talking about BTC/ETH, but can be others) and lend it out (generally for a positive APY). I can then borrow (typically USD*, but can be many other tokens) against that collateral (sometimes even for a positive APY!).
No permission needed and happens in the scope of transactions that cost pennies.
This is a massively important aspect of finance that goes beyond daily price swings. It is a relatively new aspect in crypto that has only been around for the last ~3 years or so.