Well, I'm a young man who dresses provacatively and I do that to express my confidence and comfort with my own body, and cause I like being a bit of a tease. I mean, super short shorts with a very loose tank top that has high potential for a nip slip (I'm post top surgery), see-through shirts, or an open cardigan with nothing under, is my go to summer outfit. For slightly colder weather I prefer tight pants and half open button-ups.
So it would be hypocritical of me to not think the same for women who do the same but more femininely. That it's expressing confidence and a lack of shame. But then I know that different people have different reasons for doing the same thing. I'm sure at least some do it for self-damaging reasons too, cause I know I did as a teen pre-transition.
I mean back then I dressed that way cause I wanted for others to take advantage of me, and that's not a good way to "handle" shyness, insecurities, other mental health issues and sexual frustration. It got me into trouble more than once. Even very serious trouble, as in sexual assault. However I'm sure it wasn't just my outfit and mindset that got me into that situation, but I can't deny it was a factor.
Now, yes I appreciate positive attention to dressing in revealing clothes, but it's not like I chase that. It would just be a bonus. I've learned how to handle the negative attention well. I definitely have a reputation of being promiscuous, but for me that's a good thing and something I want to keep up.
I know the question is about women specifically, but I don't think there's a huge difference between women and men expressing themselves in the same manner, at least according to my own experiences. Especially as a gay (trans) man, I get pretty much still the same kind of reactions from other men for dressing the same way now as I did before as a more or less straight girl. Perhaps sexuality can be somewhat of a factor to consider to this question as well. As I think it might be a bit different for lesbians and straight men who also dress provacatively, and surely for bisexuals and asexuals, etc too.
I did vote "They are expressing a positive self image" cause I think that's for the majority and/or most common reason, but that might just be my own assertions. Also, I have no issues what so ever with older people dressing like that either. Each to their own. I think it's a shame that we are being told that certain types of bodies are not to be shown.