You can have both. But good tool design looks at the horizon, not just at your feet.
You could deliver the same convenience in a way that’s set up to be repurposable (fullcolor /rgcolorblind) or extensible (light / grey / dark / …n) with as little difference as choosing a more mindful name.
I agree with the previous comment that the current approach lacks flexibility in achieving high contrast. It might be beneficial to consider a more general and adaptable method that can accommodate different styles or even introduce primitives for different styles in the future