Consider counter air mission. The ultimate aim is to destroy the enemy aircraft. The traditional approach was to crater the runway thus pinning the aircraft to the ground. The program then continued with further attacks on the runway with the hope of collateral damage hitting the aircraft. HAS were a counter and area denial a counter-counter.
These programs need lots of aircraft. PGM may reduce the number of aircraft needed to crater the runway and PGM can more easily plink the HAS, but you still need lots of weapons over target. 4 Paveway on a Typhoon don't cut it.