There's a "purpose of a system", but there's also a purpose which we want that system to serve, and which prompts us to correct the system should it deviate from the goals we set for it.

That is a simplistic idea that I am scared has spread far and wide.

A system is a tool, it does have a use/purpose in the simplistic sense. But how we use the tool is ultimately the crux of the issue, for we can use that hammer to build houses or tear them down, or to build concentration camps or use it simply to injure someone directly.

No, the purpose of a tool/system is generally determined by the guiding philosophy of the user or society. Unfortunately society has replaced its philosophy (at least in America) with the economic system of capitalism; i.e. capitalism for capitalisms sake.