It sharpens the lighting to make it harsh and extreme, reducing the thick/painterly (impasto-like) feel, but it doesn't turn the image into flat cel-shading or pure flat colors—instead, it amplifies the light-dark contrast (high contrast / dramatic chiaroscuro).
Aesthetically, it has a slight but noticeable effect.
It's hard to say if it's definitively good or bad, but in practice it does a nice job of balancing/seasoning the image.
CFG:Within 1 and below, the closer it gets to 1, the sharper it becomes—but if you go above 1, the light-dark contrast ramps up rapidly.
📢However, it's worth noting that a large number of quality keywords are needed, otherwise the results will be quite poor.