Suppose one of your friends puts on different clothes every day. Is there any word or phrase to describe someone like that? I think luxury is not very close to that meaning.
I think the word that describes this situation is excess:
more than is necessary, reasonable or acceptable
Another definition is:
the state or an instance of surpassing usual, proper, or specified limits : superfluity
So the adjective form is excessive--your friend could be excessive because they change their clothes so often. Or, similarly, they change their clothes excessively.
My impression is that most women and some men wear different outfits every day. I doubt that any terms suggestive of excess (like clothes horse, obsessive, fashionista) are appropriate. Regarding whether the friend in question is fashionable, stylish, vain, fickle, or irresolute, all of those words represent unrelated issues not supported by the question.
If you want non-judgmental words, normal, ordinary or clean probably are best. If you want to suggest some extra care for clothes, perhaps use fastidious. If you want to suggest a good deal of extra care for clothes, use some of those previously suggested words.
Another noun expression for such a person is clothes horse.
I think the word you're lookiong for might be obsessive.
Depending on the sense you are looking for fashionista might be appropriate.