I think the first part you wrote is a bit hard to parse but I think this is related:

I think the problematic part of most genAI use cases is validation at the end. If you're doing something that has a large amount of exploration but a small amount of validation, like this, then it's useful.

A friend was using it to learn the linux command line, that can be framed as having a single command at the end that you copy, paste and validate. That isn't perfect because the explanation could still be off and it wouldn't be validated but I think it's still a better use case than most.

If you're asking for the grand unifying theory of gravity then:

• validation isn't built into the task (so you're unlikely to do it with time).
• validation could be as time intensive as the task (so there is no efficiency gain if you validate).
• its beyond your ability to validate so if it says nice things about you then a subset of people will decide the tool is amazing.