Nothing in Pakistan happens without a reason.
And there is a reason why Dollar Dar, despite his calamitous record, enjoys such a fan following among generals, press barons, journalists, legal fraternity etc. That reason is that Dar provides connected people with a fool proof way of making money.
DD's flagship policy is to keep PKR inflated. Magnitude of PKR over-valuation can be determined by difference between rate quoted on the kerb market vs official rate quoted by SBP. Why does DD follow such a diabolical policy which is a sure-fire way of bringing about financial distress? The reason is that by keeping PKR inflated, DD can gain influence among ruling circles. Parties whom DD wants to bestow favour upon are allowed buy dollars from official channels at a lower rate and sell it at a higher rate at the kerb market. Simple as that. For example, if DD wants a favour from a general, he will ask SBP to sanction USD to the general at official rate lets say @ 100. The general can then sell USD in the open market at kerb rate lets say @150. So the general can make PKR 50 on every dollar risk free. Similarly, parties that want to take their sarmaya out of Pakistan also benefit when PKR is over valued i.e. USD can be bought cheaper.
The other skill Dar posses which is useful for the corrupt elite is that Dar is a master money-launderer. For example, banks in western jurisdictions will not want to transact with politically connected people in Pakistan i.e. politicians, generals, bureaucrats etc because banks know that these people cannot have hundreds of thousands of dollars in their bank accounts because their salaries are simply too low. Banks that operate in western jurisdictions have to pay a huge fine if they get caught for money laundering so they will restrict activities of politically connected people based in banana republic jurisdictions like Pakistan.
These restrictions create a problem for the elite because no one is crazy enough to leave their sarmaya in a country where fraudiyas like DD can become finance minister. So in steps DD who in return for quid pro quo agrees to do the needful. We have DD's own testimony on how he goes upon achieving this.
I got to watch Sharif family ghadaari very early in my professional career when I was a junior at a foreign exchange desk in Karachi. One the eve of nuclear explosion, word got around that Sharifs and their cronies were transferring millions of dollars out of Pakistan at a juncture when the country needed every single dime. Here is how the story was reported in Dawn:
https://asianstudies.github.io/area-studies/SouthAsia/SAserials/Dawn/1998/06Jun98.html#88mi
88 million withdrawn from forex accounts
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Reporter
KARACHI, June 2: A sum of $88 million is reported to have been
drawn from the foreign exchange currency accounts during May 25 to
May 28, banking circles reveal.
On May 28, the day when Pakistan blasted nuclear device in response
to five nuclear explosions by India earlier on May 11 and 13, the
government put a clamp on the foreign exchange accounts.
Banking circles say that a few senior bankers associated with the
privatized, private and foreign banks anticipated the oncoming
measures and informed their clients and obliged them by offering
various outlets for drawing foreign exchange from their accounts.
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Going back to the policy of fixed exchange rates, During the term of IK, GOP had given its word to IMF as well as to commercial creditors that Pakistan will implement a policy of market based exchange rate i.e currency will be free floating. Under directions of DD, GOP simply went back on its commitment. Liars don't pay a penalty in Pak; in fact bigger the liar greater the shaurath. In civilized world however, dishonouring of contract results in serious pain. That simply is a price you have to pay if you want to enjoy the comforts of the modern world. Unfortunately pain is what awam will feel until it develops the ability to discern the difference between patriots and charlatans.