Oh gee, thankfully THAT is nothing that I have to be concerned about; I’m just NOT very tech savvy!
In some circumstances, it is critically important that colors appear identically in two different environments (say, on a computer screen vs. when that same image is printed on a color printer). Whole businesses and people's careers are based on working that out.
But most of the time, in real life ("IRL"), we can live just fine with "close-enough" approximations, because nobody cares to get that picky about it. Especially with something aesthetically pleasing like a painting -- who really cares if a photo of the painting doesn't exactly reproduce the pigment colors when the photo is displayed on a monitor? The important thing is, does the painting, or the image of the painting, convey a reasonably accurate expression of the artist's intent, and does it evoke emotions or other reactions in the viewer that are something like what the artist intended. Art is not RGB, or CMYK, or wavelengths.
Of course, wearing my (50-yr old) physics hat, all those technical things are of compelling importance. So it all depends on the context.