> In a system run by people, the transaction could be reversed, traced, and the culprits eventually brought to justice.
The answer to your question is encoded in the very first block of the very first blockchain.
> The Times 03/Jan/2009 Chancellor on brink of second bailout for banks
https://en.bitcoin.it/wiki/Genesis_block
Some people feel like they weren't being represented by the "justice" you're talking about, so they built their own thing where all the rules are publicly viewable, and consensus is run by the community. It seemed like a weird idea at the time, but the idea got popular, and people who like this new system have moved about two trillion dollars of global wealth into it.
If you like the old way money was managed, by big institutions doing everything they could to extract wealth from the general public with no legal repercussions, then the good news is that the old system still exists. There are just some other options now too.
Also, the idea that all cryptocurrencies are some laissez-faire Randian wet dream is simply not true. An extremely diverse array of crypto governance mechanisms are being experimented with. Many run by humans, all with their own interpretations of "justice", which you can read up on and participate in at will. Governance proposals reclaim funds judged to be unfairly allocated all the time. I doubt that will happen here, because Ethereum governance is generally very harsh on people who suck at testing code, but every person who lost money here knew exactly what they were getting in to when they chose to participate.