I am sure you believe that you have an argument yet you clearly failed to consider fact that both Zulfigar and Karrar are Iranian projects done by separate entities.
What Karrar has over Zulfigar is what Zulfigar could have had were there cooperation, instead there is mediocrity.
Karrar potency is limited by higher ground pressure, increase stress and load on engine, gearbox, road wheels and tracks along autoloader having a limit on length of munition hence need for exotic solution in order to increase performance such as on APFSDS versus manual loaders like M1 Abrams or Leopard 2 or with turret basket autoloader such as K2 and Type 90 / 10.
If there was goal to have tank go from southernmost to northernmost Iranian territory then crew of Karrar would need to change damaged or broken sections of track would have to do it at minimum once if not twice while Zulfigar may not even need it once during entire trip. Thus in time of crisis Zulfigar would be more reliable than Karrar.