I do agree, but there is still a valid logic behind what is shown because it's only using the pigments that there is direct evidence on the statue for - but to stop this confusion, maybe there should be three versions of each statue at these kind of exhibitions (assuming these are all replica castings and they're not re-painting the originals!) - a blank one to appreciate the unpainted form, the reconstruction of the base layer that only has the pigments found in the crevices (what this article is complaining about), and then an artists impression of what it probably looked like properly shaded (given that we have the evidence of painted statues as shown in the article).

Then you could still have the evidentially "pure" one, but also have a more likely rendering to reduce confusion.