No you can't say that about other parties because non have been looting the nation for 30 yrs. And yes it is made up of mostly fellow kashmiris muhajirs the only punjabis they have are the ones with a significant voter bank and there for useful to remain.
We have more kashmiris in punjab than the entire valley in Iok they first settled in the countryside but in the last couple of generations have moved to the cities. Here they form a significant chunk of the population for example if I told you that at least 40% of Lahores population was made up of kashmiri muhajir that would not be inaccurate.
Over the years I have had many kashmiri friends and aquintances bragg how they got one of there own elected prime minister not once but 3 times. You see they form a significant voter block in each major city in punjab and vote in a block hence the current state of affairs.
Until we have a frank and open debate about this in the mainstream media nothing will change but also there is a chance that nawaz or mariyam and their koshur gang of thieves might return to power to continue looting.