I don't intend to imply that groundwater extraction should cease, only that this effect desperately needs to be studied further. Perhaps we can develop a way to safely replace or counterbalance the mass of the groundwater we take out. Perhaps we wont need to, and natural processes that take longer than human timescales will have negative feedback mechanisms that will gradually counteract the effect. We need more precise data than an 2 decades model can provide if we want to be able to project how this will continue. Of course we also don't want Antarctica at the equator in X thousand years. We should understand what's happening better before we define and label this as a problem problem develop and propose solutions. But the known unknown, the potential for extreme axial drift leading to mass exctinction via a "global roll," is just waiting to be investigated.