I think there are quite a few followers or enthusiasts who add their own text. I am one of those. I am guessing that many don't share what they add to the raw images, but keep their work to themselves. Since I started with scripting for some of Lazarus/Genuine9 and then Old Nick, it is the only way a frustrated artist like me can be creative with certain themes.
Now I do it for Max in the Farewell series, since I have commissioned him to continue that story. We have, in fact collaborated on it. He is still working on the art, but it is a slow process. I'm adding script to the work in two ways. One is with captions, as you can see on this thread, and the other is with separate text that leaves the images clear and unfettered. This is Melissa's Diary, which is in the Original Erotic Literature section of this forum.
We are currently working on Farewell 3, which has not been captioned yet, but I am working on the Diary.
I really wish I could do both!
I keep hoping with AI the creation of models and images will become easier, but so far? No luck.