I am biased towards long hair as a metal thing, though I TRY (and usually fail) to convince myself that the short hairs just made a choice for themselves that I should respect. I don't think metal is ALL about the hair, though it is a huge plus, dudes with long heavy f'n metal hair, they rock.
I contend that the hair gathers the metal and the longer the hair, the more metal you can take into yourself, like jellyfish! *snicker*
ok ok I'm joking! longhairs aren't like jellyfish. however! for this chick, long hair, on dudes and chicks (I'm trying to beat Danny Cecati) long hair just LOOKS better!
Well having short (no) hair is kind of a compromise between being metal and looking acceptable in a professional setting. Metal is more than just hair and looks, it's more than just music, it's a life long commitment and a way of life.
No need to feel lonely. Long hair adds beauty, creativity and makes people more visible. It is healthier for the scalp for it strengthens the scalp. Long hair adds shade and prevents skin cancer. Along with facial hair - long hair really looks good. Males and females are designed to have long hair. Don't worry about those crazy shaved head fans with the baggy things below their knees. There are still many of us long hairs out there.
The girly look by metal bands fortunately went out of style. I have read the long hair was a way to attract a female audience by identifying with them back when metal lacked a female audience. Now it is a different time. There are lots of female fans now.
Times and trends change.
It used to represent rebellion for a man to have long hair, but now it's mainstream, so many metal heads don't feel the need to grow their hair. It's just a personal preference now, not a statement.