What is fashionable is not so much that “this looks nice” and “this doesn’t”
It more of a social construct, if a large amount of people consider a dress nice and fashionable it is, if they consider Not, then it will be not.
Whether Alicia’s dress is nice or not, will depend on context.
And in this context, it’s “out of fashion” which means it was “in” at some point, just that the point in time where her dress will be consider nice has already gone by, and is inappropriate to wear. Or even considered a disaster.