Agreed. Injuries to fast bowlers happen all the time across teams yet if you look at bowlers like Cummins/Bumrah/Wood etc.. they come back just as good if not better.
Pakistani bowlers, immediately see reduction in pace, effectiveness and are simply not the same. We've seen this happen way too often recently to consider it a coincidence. It's a pattern at this point from players like Junaid who should have had a long great career but immediately lost a lot of pace and effectiveness. Look at the bowlers like Hasan Ali used to be, got injured, lost pace and hasn't been the same since. Amir had a back fracture, lost pace and had to retire from Tests to prolong his career. Faheem is another one who used to bowl at fairly decent pace and looked like a decent pace allrounder in Tests, he also had some injuries, lost pace and has been rubbish since. It doesn't just extend to fast bowlers either, just look at what happened to Haris Sohail.
Now we've seen Shaheen/Naseem/Ihsanullah injured, lost pace and effectiveness. We can't keep blaming the players because it's not a one-off. It's a pattern that exists with PCB and its medical department. Calling it third class would be generous and I think there's simply a lack of professionalism and care by PCB for its players. We clearly saw Shaheen left on his own to deal with a serious injury and he was even paying the bills himself for it, which is so ridiculous. Because of the quantity of players in Pakistan, PCB disregards players who get injured and seem happy with finding the next guy mentality instead of preserving what you have. This extends to the development of players too, if they don't think you are not good enough, they will look for another guy instead of putting time in to develop and enhance the players skills & development.