Looked at in that light it could be seen as a simplification, by reducing separate systems like cruise control, idle speed control (and the torque limiting, traction control and top speed limiting) into a single system.
I suspect that there are also benefits in controlling exhaust emissions with things like the rate of throttle close on decel.
Another one is that dips in the power/torque curves can be masked (which may be related to driveability issues generated in controlling emissions).
Parking speed throttle response can be made less sensitive.
There is no possibility of a customer accelerating and braking at the same time (ask Audi about that
) as the system is disabled with a brake switch (or switches with redundancy for safety). That also precludes left foot braking, so no more FWD Scandinavian flicks :( .
I agree that sooner or later they will be hacked to allow alteration of response.
Here'* an idea: a progressive N2O system related solely to accelerator pedal movement, much easier (only possible?) with FBW.
As an observation, the ones I have any knowledge of work by both opening and closing the throttle, with the default throttle position setting a fast idle. This is to allow a 'limp home' back up, with very much reduced power, if the system fails.