Network changes because of mergers, acquisitions, and divestment can be very disruptive to the network if not carried out carefully. When an organization sells parts of its business, it must detach…

Redundant design improves fault tolerance and availability but does not reduce the blast radius or complexity of detaching a network segment during a divestment.

A modular design organizes the network into clearly defined modules or building blocks - such as a campus module, WAN module, or data center module - each with well-defined interfaces and limited interdependencies. When a business unit is divested, the corresponding network module can be cleanly separated without cascading impact on the rest of the infrastructure. This containment of change is the primary purpose of modularity in enterprise network design.

A less complex design may reduce operational overhead generally but does not specifically provide the isolation boundaries needed to safely detach portions of a network.

Routed access design is a specific campus topology choice that improves scalability and eliminates Spanning Tree issues, but it does not inherently address the segmentation needed for divestment scenarios.