low bounce is due to clay content in soil, you need to have the right mix of clay so the soil is hard and bouncy. higher clay content also means that the pitches hold more water. pakistan doesnt have the right soil for fast bouncy tracks so historically pak relied on reverse swing and spin, from the rough square and pitches falling apart.
however Pakistani curators think putting grass on a low clay content pitch will make it bowling-friendly, when it has the opposite effect, the grass holds the pitch together and it doesnt deteriorate, the pitch become quick and true paced which is ideal for batsmen when the ball doesnt bounce high.
also the hinterland locations of most grounds means that their is rarely any breeze which could aid swing bowling, and topped off with using a kookaburra where the seam disappeared after ten overs and your pretty much got a perfect receipt to kill fast bowlers, who, understandably, want to sand bag on these pitches.
the PCB is an unbelievably incompetent institution.