There are many names. Philosopher-King, bureaucrat, central planner, ruler, President, Czar, Prime Minister, Pasha, Amir al-Mu’minin, Amir al-umara, Al-Malik, Shahenshah?
The person would be supported by an educated council (of Guardians?).
The key word here is benevolent.
If that person would do things that you yourself, would have chosen, what is the immorality in that? In other words, the central technocrat is serving you and YOUR interests.