"Just like how you might measure productivity of a warehouse employee by the number of items moved per hour. Of course if someone just throws things across the warehouse or moves things that dont need to be moved they will maximize this metric, but that would be doing the job wrong - which is not a productivity measurement problem."

I fail to see how having a measurement that clearly doesn't measure what is actually produced isn't exactly a productivity measurement problem. If your measurement is defeated by someone doing their job badly, what use is it?