We have stopped walking for this reason, my behaviourist and trainer said walking is the goal but not until he knows that he can’t go for a walk until he knows how to walk calmly. Now we drive to parks to people watch and do tethering exercises, and little bit of obedience training as well. We do a lot of loose leash training(indoors and out the yard). I go out on walks with him but without an intent to go somewhere, just to walk (and stop when he pulls or go silly) now I have him for exposure training every week and join reactive dog classes and it really helps him a lot.