When I think someone is 'attention seeking' it's always a girl, and the girl is expressing a need to be valued. I've noticed girls who are in foster care or are in an unloving home environment are often the ones who display this most intensely. Boys tend to seek attention too, but in a different way (acting out, showing off, etc).
Teenaged girls or young women who post selfies every.single.day. (often with kissie lips) are seeking attention, using their appearance to gain approval or show they have value.
So 'attention seeking' is definitely a thing. And it seems to be more so for girls or women. Maybe it would be better phrased as seeking value or affirmation? But it clearly should not be used as a put-down or a way to dismiss what a woman is trying to express (as in 'she's just attention-seeking'). And it surely should not be used to dismiss a gay person's need to make a statement through behaviors and attire as they work through their sexual identity.
On edit - A woman's demand to be heard and valued as an equal in society is NOT 'attention-seeking,' and should never be referred to as such.