The Volvo might have had a 'hard' limiter, similar to one on the Mercedes. One could set a max speed via the cluster menu, that could not be overridden. The Mercedes also had a 'soft' limiter, more easily set via a column stalk, that could be overridden by a firm push on the throttle.
The up-coming mandatory limiters on new cars will be set via gps/camera to the local speed limit but can be overridden by the throttle or disabled altogether. I imagine if disabled it would re-enable at each IGN cycle, similar to many stop/start eco systems.