Perfect correctness is what you'd expect from a computer. I could write a program that solved it - and that would be an indication of my creativity as a human solving something that I haven't encountered before. Incidentally, that's also how it approached solving the block problem (by writing a program).

If you ask me the goat, wolf, cabbage problem I'd be able to recite (as an xkcd fan https://xkcd.com/1134/ and https://xkcd.com/2348/ and the exploration of what else it could do). However, if someone hasn't seen the problem before it could be a useful tool at seeing how they approach solving it.

The question of how does it tackle a new problem is one of creativity and exploration of thought in a new (untrained) domain.

A possible claim of "well, it's been trained on the meta-problem of how to solve problems that weren't in its training set" would get a side eye.

For the "ball" being the answer... consider the second response to https://chatgpt.com/share/6920b9e2-764c-8011-a14a-012e97573f... (make sure you click on the "Thought for 1m 5s" to get the internal process)