This is super cool, I've wondered if this wort of thing could be possible and I guess it is. The applications given are funny though. I can't think of any applications either, but "helping people with color-blindness" reads like the ol' search and rescue excuse [1]. I think they're talking about shifting colors around so less color is perceived in the wavelengths they can't see?

[1] https://xkcd.com/2128/

Three month old article.

What is most of interest to me in this research is that having a handle on stable and bio-safe chemistry that is reactive in near-visible spectra,

allows for a future wherein that chemistry is baked into additional cones,

allowing for polychromacy,

which might conceivably result in new qualia ("colors as they are perceived by the viewer" as in classic dorm-room arguments about whether one person's blue is another's red).

It'd be nice for our civilization to persist long enough, and to live long enough, to not just be around when that happens but have opportunity to try it out.

I think of the Radio Shack passive infrared card.

It was a plastic card that you could place under a light to "charge" and then if you aimed a remote control at it and pressed a button - it would glow red.

It would kick up infrared passively into the visible light spectrum.