The point is, we wouldn't know if we had one because that the interest rates are a number being chosen by a small committee. We might not have a savings glut, we might have a natural rate of interest at 10% that is being suppressed by central banks.
There is a minor pension crisis in the United States and their infrastructure is not in great shape. That doesn't make it look like there is a savings glut. There is a lot that needs to be done.