This is almost a philosophical debate 
GP can indeed make it possible to do without a lot of controllers (even nor at all), if that is your aim.
Personally as a guitarist, using GP only for live, I can’t do anything without controllers or else it’s a live simulation using automations without any real time control, which is of no interest to me.
My approach is not to invariably reproduce the same set of sounds, effects, etc., but to use them in real time by varying the parameters according to the context in the present moment, by deciding to use such or such instrument, to apply my sensitivity according to my playing partners or in interactivity with the public.
My pedalboard composed only of controllers allows me to concretize this approach by giving me a total control on my game.
No handy, no candy. No feet, no sweets 
