Regardless, I apologize if I misunderstood "writing code", I take that to mean "typing code" as the other stuff we do around is more "problem solving" than anything else, regardless of what the activity is (thinking, designing, troubleshooting, etc).
An interesting HN search for comments with "I love writing code" that has some false-positives, but has programmers stating clearly they like the action of manually typing code: https://hn.algolia.com/?dateRange=all&page=0&prefix=false&qu...
Nobody enjoys anything that isn't problem-solving, with debatable exceptions for drugs and hormones. Fun is learning. The learning is either subtle and inexplicit, or partly subtle and inexplicit. You engage with a medium, you interact with the work, you make edits, you learn stuff. If you're shepherding an AI then you do all that on a different level, in a different way, a way that isn't better as such. You're doing a different thing. (Meanwhile, the AI doesn't have any fun.)