Most observers would agree that replacing old copper with new optical fiber is a good idea. As with every public policy framework, not everybody always agrees, though.
Some advocate keeping copper in place. Non-facilities-based local access providers in the U.S. market want copper to remain in place, so they can use that copper to compete with the owners of the copper access facilities.
And some of the same policy advocates who generally complain that fiber is not being installed fast enough, often always support more investment in new copper access, moves that make the business case for transition to all-fiber facilities even harder.
So even if it remains a logical public policy stance to move as expeditiously as possible to all-fiber fixed networks, there always is opposition.
For every public purpose, there are corresponding private interests. Some of those private interests actually delay the fastest-possible transition to all-fiber access in the fixed network.