I suppose it's much more difficult to apply to a non-FBW aircraft. It would have to be quite a complex system to stop a damaging yaw excursion. There's always the possibility that the control input needed to stop swinging going out of limits would exceed structural limits for the fin/rudder anyway. The momentum for this event could be built up over several cycles and be hard to dissipate all at once.
A FBW system could/does model this and stop it getting out-of-hand in the first place.