Not sure what is disingenouous about it... The website is showing the current time encoded as colour, with some animation to make it look good. Its not a colour guessing game :)
> Since pure hue variations in RGB comprise less values than the total number of seconds in a day, colors are further modulated each second to show a distintive gamut of colors for every different moment in the day.
> Variations are based on phased sine functions that respond to each individual color, the fine modulation and luminosity.