No, they absolutely did not just do that in this case, although that was the SD plan. If you prompt for "painterly, oil painting, thick brush strokes, impressionistic oil painting style" to flux, you will get ... anime-ish renderings.
That's not what I'm talking about, SDXL you can literally prompt a famous artists entire style and mix and match them, even conceptual artists and sculptors.
It feels like they just removed names from the datasets to make it worse at recreating famous people and artists.