I have been curious about this particular recent feature.
Does brightly colored/neon hair indicate the person is part of some particular group?
My exposure to this trend has been primarily with people on the internet, specifically Twitter and it seems to be predominantly women, and predominantly associated with being outspoken on modern civil rights issues.
That is the most positive way I have seen somebody frame them. I guess they would even call themselves social activists...
The hair style is both a signal to others and a modest act of rebellion against societal norms. Modest because similar hairstyles have been around for decades in older countercultures.
Yes. The "I'm non-conformist and quirky!" girl.
Of course, they're "quirky" exactly the same way as all the other "quirky" girls.