The customer should not need the architecture lesson

Builders can become attached to an elegant architecture and assume the customer will value it for the same reasons. Usually they will not.

The architecture matters only if it produces something the customer can feel: privacy, lower cost, faster response, resilience, control, or a capability they could not get before.

If explaining the value requires explaining the whole diagram, the value proposition probably is not ready yet.

The customer may eventually care how the system works. They should not need the architecture lesson before they can understand why it matters.