No blockchain can ever guarantee there's any visibility or accountability. Defi means are only useful to trade cryptos for other cryptos, and you only have visibility if no one launders the money through crypto mixers. Once you want to cash out and trade your cryptos for any real assets, like buying a pizza, you instantly lose visibility again because all that has to happen off chain. Just because something is a tradfi problem doesn't mean it also can't be a defi problem. In this case, and in a lot of other cases, it's both. Blockchains cannot solve this problem in any meaningful way because you can never force everything to go through that chain. Fraudsters will just move it off the chain and lie about it, and that instantly puts you back into a spot where blockchains aren't doing anything for you.

I argue this is what they wanted out of blockchains. I remember all the rumblings in the days of Silk Road and Mt Gox. The enthusiasts that are responsible for propagating this system into today wanted it to be a wild west where anything goes. They said all the same things back then. I heard people saying it was good that Mt Gox got hacked because it meant all the scammers got what they deserved and they learned their lesson. Well, they didn't! It continued to be a wild west and more scammers just showed up. They'll keep scamming and they won't stop as long as they can make money from it. I don't know why crypto people are so reluctant to acknowledge this. Scammers seek out anywhere they can latch onto and they don't leave until forcibly removed. If a malicious person finds a risk-free way to get free money from unsuspecting victims, with no downsides, why would they ever want to stop?