> What is unsafe about imagining this scenario? Why should we not have this tool or imaginative/subjective interpreter?

Probably precision-recall tradeoff issue.

> why can't the public interactive implementation, and why does it lie about its abilities as its reason for not answering?

OpenAI is probably using some kind filter mechanism (which may be induced through some special tuning, or some kind of "hack" layer put on top off GPT -- may be it checks perplexity or something combined with some other keywords detection/regex and/or ml-classification-based filters). Whatever the filter mechanism is isn't perfect. They are also shifting the mechanism to prevent exploits (that users are coming up with). This may lead to "overfiltering" (harming recall) resulting in non-answers even w.r.t innocuous questions.

More work is probably put into ChatGPT because it's the current most public facing technology and OpenAI is probably trying to err on the side of caution (avoid controversies even if that means less interesting of a model that often avoids even relatively innocuous questiosn). Most are probably not gonna go deep into other apis to bypass.

Though, it's a wonder where the arms race between users finding exploits and OpenAI finding counter-exploits will lead to (perhaps, a highly neutered version).

I am just speculating; no idea what they are doing.