This strikes me as a somewhat curious attempt to explain away quite startling images. If these “formations” supposedly took 5 million years underwater to form, given their shallow depth, one must ask what would be the effect of long periods of above ground exposure over that time period. Only 12,000 years ago, these “formations” would have been well above sea level–as everyone must agree given the geological record. In fact, except for the last 10,000 years, sea levels haven‘t been as high as they are now for 110,000 years!
Given the overall distribution of sea levels historically over the last 5 million years, it is certain that these “formations” would have spent a greater amount of time out of the water than they did in the water. For the virtual entirety of the last 3 million years they would have been above ground.
While the hypothesis is framed in such a way as to fit the possibility that these “formations” formed in the period of generally high sea levels from 5-3 million years ago, we should remain skeptical of such an account until it provides an explanation as to the morphological consequences of a greater period of above ground exposure. I do not have access to the original article so I do not know what, if any, explanation the researchers provide regarding this process of supposed above ground weathering that doubtlessly must have occurred for their hypothesis to have any validity whatsoever (and to a certain degree I hold the authors of this article responsible for my own ignorance in this regard given that they chose not to make their article open access even though the journal of publication allows for such a possibility). I do wonder however just exactly what sort of standards of comparison or reproducibility exist for establishing such a peculiar formation scenario as being definitively at work in this particular instance. Indeed, one wonders just what sort of evidence would be necessary so as to make the hypothesis in question a uniquely plausible explanation for the phenomenon in question.