The wealth of Punjabis in Pakistan is because of the fiefdom that still exists in Pakistan. It has nothing to do witheir "hard work". It is the hard work of the serfs serving Punjabi zamindars.
Punjab had the most successful land reforms. Only a handful of feudal lords remain in Punjab. The fief structure is the worst in Sindh and Balochistan. I think in Balochistan, a normal Baloch can't even own land.