Yes and everybody in star wars looks normal and like a natural person you’d see who didn’t do anything to alter their own appearance!
People in Star Wars generally look normal for their contextual environment. Holdo is on a Resistance capital ship fleeing the First Order. She’s not on Canto Bight. And no other human in Star Wars canon bothers to dye their hair wild colors. Why she would dye her hair purple as well as pile her hair into that crazy hairspray-intensive hairdo, while in the circumstance she faces makes no sense.
Recoloring her hair to a normal shade would make her more believable in such a serious situation.
Looking like she belongs with the fat cat weapons dealers is kind of the point though. Poe (and the audience) don’t trust her because she doesn’t feel like a part of the Resistance. If she were just another commander, would we have bought Poe becoming mutinous?