The question is, do YOU need a fan?
The rooms have AC and heat. Unless you need something blowing on you or need it for white noise, it's just taking up space in your suitcase.
Just asking because videos and blogs sometimes overhype things people "must have" and they're not really musts.
Saw someone else asking about buying luggage tag holders-- which you don't need for
DCL because they use the sticky luggage tags similar to airlines.
(and there's the weekly question about lugging water onboard)
Happy Cruising!