“More professional looking” has historically been used to justify racism and sexism.
Looking like a professional means looking like the person who knows how to do this job, whatever it is. Professionals come in all sizes, shapes, and colors. If I have a different mental image of “looking like a professional plumber” to “looking like a professional nurse” to “looking like a professional accountant,” that’s my bias and shouldn’t dictate who can be those things. Nor how they can wear their hair except for safety.
It’s not like she’s unclean, or doing her job poorly, or harassing the customers.