What is the primary purpose of a Plan Region in Revit?

The primary purpose of a Plan Region in Revit is indeed closely related to managing the visibility of certain building elements. A Plan Region allows users to create specific areas within a floor plan view where different visibility settings can be applied. This is particularly useful in larger or more complex building designs where particular sections may require unique detail levels or visibility adjustments that differ from the overall view.

By utilizing a Plan Region, designers can selectively show or hide elements, adjust the detail level, and control the appearance of specific sections without altering the entire view settings for the plan. This feature enhances the clarity and organization of the construction documents, ensuring that necessary annotations and details are presented effectively for various stakeholders.