Programs are fundamentally lists of instructions. LLMs are very good at building these lists. That it performs well when you say "Build a list you've seen before, but do it in a slightly different way this time. Here's the exact way I want you to do it." is not surprising. I would honestly be surprised if it couldn't do it.

As the other commenter suggested, a genuinely novel scientific idea would be surprising. A new style of art (think Picasso or Pollack coming along), not just an iteration on Ghibli, would be surprising. That's actual creativity.