Fixed and rotating naval radars solve different system problems

Is a rotating naval radar inherently better than a fixed array?

No. Rotating arrays retain some mission-specific advantages, while capable fixed AESA systems provide broad coverage with fewer mechanical failure points.

Radar choice depends on the complete system and the mission. Some rotating arrays offer useful pointing geometry for tasks such as ballistic-missile tracking, while fixed active electronically scanned arrays can reproduce much of that capability when given sufficient power and coverage. Removing mechanical rotation also removes equipment that can break or suffer shock damage. This is a reason to expect greater use of fixed arrays, although good and poor implementations exist in both categories.