Using the color wheel to set the light color, I see about 10-15 distinct colors. So where do the 16 million colors come in? Obviously much of this is marketing as I doubt the human eye can distinguish between so many similar shades, but I also don’t think the color wheel is calibrated that finely so moving it a fraction of an inch with the green area will actually change anything. Or put another way, I can move my finger a small amount and the color does not change at all.
I suppose if you enter color codes you can create more colors that the color wheel cannot produce, but really 16 million? I am skeptical.