Yes, BT was divided into two business units to enable this process. They unlawfully colluded with each other in order to stop any reseller from being able to charge less than the BT retail offering. Result: terrible infrastructure investment and no competition.

Or the other way round - have a thin public service to interact with users, subcontracting all the heavy lifting to competitive bidders working to a rigid specification. You set up a monopsony rather than a monopoly, letting the public rinse the companies for once. This is how Transport for London provides bus and Docklands Light Railway services, and it works very well.