Idealy, for me as a layperson who is only going to see these in a museum, I'd love to see a series of pieces...

First, the original, untouched (preserved but not restored?) sculpture.

Second, the reproductions highlighted in the article. With appropriate notations about "these are the base layers, not complete, etc"

And third, a best-guess at what the original could have looked like, based on the first two. Yes, this might be wrong and need to change over time.

They show us what the base layers were, and what pigments of the day looked like.

It may be an academic point. But they are academics.

Well they might as well show the texture of unprocessed marble as well. This is not particularly different.

I mean, showing the texture of the underlying stone is how the vast majority of statues from classical antiquity are displayed, and indeed how most pastiches are created.

(and half the objection to the paint jobs comes from the fact we've come to incorrectly associate decorative elements from the classical period with the colours of bare stone)

Associating them with garishly and almost certainly inaccurately (based on pretty much all the indirect evidence we have) painted sculptures doesn't seem like much of an improvement, though?

I totally agree with. This is not a reconstruction because the shading, detail and subtler colors are completely left off. It's just a reconstruction of the statue as it would have been in an incomplete state!