There's a causal relationship there, often expressed in some form of the idea "the pendulum swings". Heresy-hunting inevitably produces the backlash. It's fun during the upswing to push harder to punish the heretics more and harder, but the result is that the next phase of whiplash is even worse. As well as the inevitable attempt to hold on even harder and with more righteous fury as the grasp on power fades.

Of course if you try to imagine how to coordinate an awareness that people need to settle down a bit right in the middle of a purity spiral, well, one might as well try to hold back the ocean. You start to see how a something like psychohistory is at least an appealing idea.