It’s a bit silly for this situation, but the basic idea of moving from “weapon” to “weapon system” is reasonable, in a 20th century kind of way.

Basically, WWII showed planners they were in the war business not in the ship/plane/tank business. Take navies, for example. For most of the history of the professional navy, the overwhelming cognitive container for “unit in the navy” was a ship. Planners paid for ships to be laid down, admirals planned where they went and captains were responsible for them in all regards. You could reasonable count a navy’s capability by counting the kind and number of their ships: thus and such frigates, ships of the line, etc. However, even before the 20th century naval planners knew and acted like ships weren’t atomic: counting guns on ships of the line as a distinguishing feature or planning a sortie based on available marines both herald what would come later. But mostly we thought of ships as ships. If the enemy was to have 3 battlecruisers then we ought to have 4.

WWII shuffled all that around. At the scale of fighting and industrial demand, the idea of a “ship” or a “tank” or a “fighter” as a unit of analysis started to look tenuous. Successful commanders and (especially) planners noticed that the math worked out much better if we considered units of analysis larger than individual technological objects. The immediate consequence is one starts to think in terms of weapons delivery to the enemy and not the Sherman tank. The primary concerns then (often but not always) shift from characteristics of the weapon as a weapon to: can this system as a collective be built cheaply, can it be deployed + trained on easily, and can it achieve goals in mixed employment.

The same basic idea animated the operations research revolution in warfare, the bam changes from thing to thing_system or thing_platform are consequences of that.