There are some use cases. For example, if you want to do some non-KYC small leverage few month long position on a BTC vs fiat, you can borrow stablecoins against BTC loan and then use them to purchase more BTC. Or you could borrow fiat for daily expenses against BTC loan instead of selling BTC, with hope that BTC will go up, and you will be able to give back loan cheaper. Most important is to look at non-KYC non-custodial platforms (2-of-3 or 3-of-4 multisig is ok, giving up custody of your sats isn't). Good platforms for these cases are lend.hodlhodl.com and debifi.com. There are some others, I just don't recall the names from my head right now.