The problem with saying LLMs are AI - let alone a step towards AGI - is that they cannot create.
I'm not sure if there's an intrinsic difference between humans and LLMs here. What we, including children, do is just re-hashing, re-combinating what they've seen / heard. I think it would be very difficult to prove that people come up with completely brand-new ideas without any external inspiration (= training input).
The examples are not really convincing of your point. The GPT output is pretty good given the ask, I'm not sure if my daughter would fare better.