That is how scholarship works. It’s like a math proof: they’re interested in proving the base case. If someone else wants to do more speculative work to theorize what a well-painted version would look like, that would be super cool, but it wouldn’t be scholarship.
“The reason I’m totally misleading you with a speculative example is because of scholarship.”
No way. When they engage the public, they are not longer exclusively scholars. They responsible for conveying the best truth they can to non-experts.
A journal paper can be misunderstood when the reader lacks the context to interpret it. Out in the public square, that is not the reader’s fault anymore.
"Dance your PhD" exists for several reasons, but one of them is to point out that the divorce between scholarship and art in some academic fields isn't "required" but an accident of how we separated colleges and how hard it can be to do multi-disciplinary work.
You can do both: prove the base case and reach across the aisle to the art college next door to see if someone is interested in the follow up "creative exercise". You can present both "here's what we can prove" and "here's an extrapolation by a skilled artist of what additional layering/contouring might have done".
I would agree with you, but archeologists often classify finds as "for ritual purposes" without any proof or evidence that it was used in a ritual, without specifying what ritual is involved, or how the find would be used in the ritual.
Likewise archeologists will classify finds as tools when they don't have nearly enough knowledge about the craft in question to be able to do this properly (see the extensive mis-classification of weaving swords/beaters as weapons [0], but there are many other cases).
So I'm a little reluctant to cut them some slack and say "this is how scholarship" works when they get all petulant about including colours that we know the ancients had, in ways we know they used them, for this kind of reconstruction.
[0] https://www.academia.edu/67863215/Weapon_or_Weaving_Swords_a...
And that's a fine standard to maintain when you're writing an academic paper.
When you are instead putting together a museum exhibition intended for the general public, and you observe over and over again that they will interpret your work as representing what the statues actually looked like, it is irresponsible to keep giving them that impression.
It's not an either/or question. They could do some of the statues with just the pure archaeological approach of only using the paints they found in the crevices, and do others in a layered approach that is more speculative but probably closer to how they actually looked. If they did that, this article would not be necessary.