I always thought the fictional Trek job of Holo-novel writer was an interesting premise, especially in a society where money didn't exist.
So, yes, you have the technology to make realistic-looking holograms. You have things like holo-imagers that can take 3D pictures of objects in real space. You have AI 3D image creation technology that can generate people or objects in a way that they seem convincingly real. Not only that, but you have... some level of scene generation "computer, I want you to create a town typical of France in the 1400s", which seems to work well enough for surface level stuff. The holodeck in Star Trek never seemed good with open-ended prompts like "Computer, tell me a bedtime story" that weren't already pre-programmed works.
But - someone has to put all the pieces together to actually make it a reality. In some ways, it's pretty similar to modern VR headsets where you have the ability to create things in a virtual 3D space and make them fairly realistic - but you still need a massive team of talent to make something worthwhile. So were holo-novelists in Trek really just creative storytellers (similar to modern day novelists) that also happened to know how to program holodecks? Instead of writing characters, you would actually have to program their motivations, dreams, and goals in addition to things like speech / accents / dress or costume. If you have more than a handful of characters, how do you stop the whole thing from going off the rails? With the user input it throws a wrench into the context. What happens if Dixon Hill actually shoots the girl in the doorway before the adventure starts? Do you have to write / program for that eventuality? How could any story possibly make sense if there are infinite outcomes?
And to answer OPs question, sex stuff.