if what you're suggesting is true, then more important instructions like "Don't delete the production database" are a problem. I shouldn't need to consider how to phrase "Don't delete the production database" in a positive manner. Isn't the point of an AI agent that it understands my intent and I don't need to hold its hand? I'm not saying your suggestion is wrong, I just think that suggests a limit to what these tools should be used for if that's the case.
My guess though is that it probably ignores some of the positive instructions too, and the hardcore AI users mostly don't notice because they probably aren't reviewing the work.
These are still stochastic machines, guardrails must be inserted at the system level.
They are getting better every day about managing their own guardrails, so we will get there eventually.
There's a really major problem with the concept of human-in-the-loop though, which is just that humans are not built for that that kind of work. It's like all those tests against the TSA where they manage to sneak something through that should have been caught. But the problem is, a TSA agent sees probably like 1000 things they can ignore to the 1 thing they need to look at, and it's easy to just start rubber stamping things.