Why distant naval commanders still need delegated authority

Did Victorian communications require a level of delegation that modern naval command no longer needs?

No. Modern communications can still produce damaging remote micromanagement, so an empowered on-scene commander remains necessary to coordinate subordinate groups.

Slower Victorian communications demanded delegation, but rapid modern communications have not removed that need. Excessive control from home remains dangerous even when messages travel quickly. In the Falklands War, the absence of a single senior task-force commander in the south allowed different authorities at home to send direction to separate task-group commanders. An on-scene commander needs adequate staff and authority while the government concentrates on wider strategic policy.