There’s also a level of “there isn’t actually a written record of the obvious use for this so we can’t responsibly call it a dildo” and ritual being an incredibly vague descriptor. It might be an overcorrection to the long history of wildly inaccurate fetishization of “exotic” cultures in anthropology.
To oversimplify: there was not a demonstrable process that could explain the movement of huge sheets of solid rock, that’s where the reluctance came from. It wasn’t until the ocean floor mapping of the 60s that we understood the non-random nature earthquakes and the existence of mid-ocean ridges that lead the scientific community to accept “seafloor spreading” as the mechanism of Alfred Wegener’s proposed continental drift.