I think concepts from impedance matching could also be loosely applied to other areas, for example:

- How veins in organisms branch out to give "energy" to different areas while being the right size for the required supplies

- How people can adapt and communicate with simpler words but taking more time. The optimum is when both parties are "matched"

- Information theory, data across a channel needs to be sent at a rate lower than its capacity, otherwise it's "rejected"

- In organizations, when a message needs to be passed from one area to another one, each impedance mismatch between individuals can lead to some "information bounce" and make it harder to get a message/idea across

- When politics adopt a measure, there's an impedance mismatch when people aren't fully onboard

It's a bit methaphorical but the overall idea is that efficient transfer across an interface requires compatibility between the source and destination. Incompatibilities produce some sort of "reflections", "distortions" or "backpressure".