More updates per second to each pixel means each pixel is more faithfully tracking the real-life image, which in turn allows the eye to more accurately interpol

More updates per second to each pixel means each pixel is more faithfully tracking the real-life image, which in turn allows the eye to more accurately interpolate spatial details in the displayed picture. As you say, for a truly static scene there is no difference. In practise there is always noise in the picture, so even in static scenes a higher frame rate will tend to reduce noise by averaging.