> it doesn't explain why OpenAI wouldn't have noticed traffic getting out of their "sandbox" when they knew it wasn't supposed to.

As I understand it, there was supposed to be traffic; the sandbox allowed GET requests. So perhaps some sophisticated alarm could have noticed it (an anomaly detector? some clever heuristic that looks at domains?) but not a naive one.

How sophisticated to we need to be to know we can do write actions with a GET? Does nobody in AI know anything about HTTP?

Any basic LLM told to evaluate the traffic against the actual goal would have been able to flag this.