Were they correct or incorrect in this? Whatever your answer, why do you hold that opinion?

I work for Mozilla. We fixed a ton of security vulnerabilities that Mythos found during its early period. So my bias is to be sympathetic to Anthropic's warnings.

If I were in an organization that did not have access to Mythos during that period, I would probably be biased the other way: "great, now other people have access to a tool that could probably poke holes in my security perimeter, and I'm not allowed to use them myself."

Both biases are understandable. I'm not sure who to look to for a usefully objective 3rd party opinion. And it's not like one "side" is right and the other is wrong, either. It seems like the best we can do is to justify our positions with data. (Which is itself kind of hard; the detailed information that would be relevant here is understandably sensitive, and I don't have access to most of it even for my organization. I don't even personally have access to any unfettered Anthropic models. The bugs coming in from people who do are plenty enough to keep me busy.)

Also, I'll note that even with my bias, I wouldn't claim a threat to civilization. But even the leakage after the controlled release seems a lot worse than the Y2K problem ever turned out to be, and I will note that whatever you think of Anthropic, it's clear that OpenAI is going to let the AIs cause as much damage as they need to in order to get good training and evaluations. I'm sure they're trying to keep them contained, but the evidence shows that they're only trying up to the point where it interferes with their evaluations.