Crypto only solves problems crypto itself created. DeFi is a perfect example of that.
The reason is that blockchain can only offer its trustless, decentralized and permissionless guarantees to things that are wholly representable on-chain. As soon as you try and sync it with the real world, the real world is the source of truth and the chain representation is meaningless.
Further, by boat anchoring solutions to the fundamental inefficiencies of blockchain, you leave your chain solutions at a material disadvantage to centralized, permissioned solutions anyways. This creates huge adverse selection bias, leaving only the criminals and scammers using it.
Concrete example: Sia has 800TB of storage - total! - in spite of an $800M market cap and millions spent on R&D. You could achieve the same result with a half of a 1U rack of hard drives and $40,000 - or a few bucks on AWS. Why? Because why on earth would anyone use it?
On the other hand, Chia has 1.5 exabytes of wasted hard drive capacity loaded up with bingo cards lol.
This is crypto.
DeFi is particularly fun, it's basically just decentralized 2008, a way to extend way too much leverage to people who simply should not have it, in exchange for fanciful 3-digit percentage APR to lenders.
It's all a damn mess.