Applying a contrasty tone curve to a simple, uncorrected matrix profile creates hue twists and saturation issues (“colors change when you make exposure [SIC i.e. brightness] adjustments”). Look-up tables are meant to correct for those phenomena in a perceptual way (not accurate, but visually pleasing).
It has the look we are accustomed to by years of visual conditioning. The tone curve lightened certain areas and darkened other areas (global contrast) and caused the increase in saturation, and the LUT corrected certain hues in a non-linear way to make the image look “pleasing”.