That would be a sound argument, IF not for the fact that everybody seems to perfectly know about these systems whenever they appear during battle.
If you want to argue the effecieny of a certain model/feature, then that surely can be attributed to the builder´s skills. But the complete lack of even trying to incorporate such features? Makes no sense. If I were a gundam fighter, Id chose the strongest model, build it to my best skills and train with it.