I don't know when it changed, but the mouthfeel now is completely different from what it was back in the late 90's.

BoPs pizza used to have what looked like course cornstarch on the bottom that gave it a crunchy, almost gritty texture. Without it the doughiness of the crust is more pronounced.

They also used to have hot sauce at the tables, which went a long way towards softening the sweetness of their sauce.