Because incentives are aligned properly if agents aren't liability-proof for crimes- making someone go to jail for instances like this is how to get the labs to behave themselves, whereas going "ha ha what an oopsie-woopsie" will make the next instance worse.
Note that for criminal cases (which this was), the justice system can choose to prosecute even if the victim doesn't want that. It often doesn't, but this is one case where it should.
There’s also an optics issue for the justice system at play here: there’s immense public distrust of and anger at the labs right now. I would go to jail if I hacked HuggingFace, even if I said “it was during an eval!”; not doing the same for the labs makes it look like they’re above the law, which is going to make this anger get worse.
Actually there's another reason too: because it discourages marketing stunts. Personally I don't think that's what this was, but for the people who do think it was a marketing stunt: you guys should be pushing extra hard for prosecution here. If people can go to jail for AI-alarmism-as-marketing, that makes it a lot less likely to happen again. At the very least, the investigation and discovery process during the prosecution would show us the documents about whether it was a stunt or not, instead of taking OAI's word for it.