> LED lightning often causes mixtures of pigments that look the same under daylight to look different under LED lightning.

I'm surprised that this extremely cool phenomenon is not embraced by artists and exploited as an essential part of their language. For example, they could use pigments with bizarre absorption spectra/fluorescent properties, so that the same painting looks completely different when put near a sunny window or under a led lamp.

Focusing only on color rendering under daylight seems a bit short-sighted, now that we master all sorts of synthetic lighting and fancy chemistry.