I believe, at some point (early last year, if my brain isn’t doing a funny), the industry generally configured their models to use this glossy cartoon style, if the user doesn’t specify anything else, because it’s a style the models can do fairly well.

Their largest training set is humans, but mistakes on humans look horrid, due to Uncanny Valley, so the cartoon style avoids that. It also requires relatively few details that the model can get wrong or that the user would have to correct in their prompt (like perspective, light angle etc.).

Well, and this specific cartoon style allows them to still keep lots of detailing where mistakes don’t matter, like on the hair, so that it doesn’t look entirely simplistic…