OTOH for something like this to have been constructed ~3800 years ago suggests that it was probably the product of a more sophisticated kingdom than a couple of sheep herders would have had either the means or inclination to construct.
That it has survived this long - well, maybe a bias, but also may indicate that it was well cared for, and stored away carefully at some point, such that it survived the next few millennia.
Not everything made during the Bronze Age was made out of bronze.
Case in point, as described in the article, this artefact was made of rock.
Still, a rock slab map is a considerable investment in creating time, and remains relatively stable over time - so the basic argument still stands.