Hey, I'll 'fess up. Female here--but not a redhead!
I think the really hardcore fans over the past, gulp, 20 years in the wilderness have tended to be male. Certainly there's not a 30-to-1 gender ratio among casual fans.
Perhaps this sort of forum appeals more to men, on average, because men are less chatty in person? Because there's something of a male style to the banter, due to those posting being overwhelmingly male? (The male geek factor.) Because you're more likely to feel comfortable posting if you played 'ball yourself?
It took me years of lurking before I actually signed up and posted comments, not only in sports, but in political and professional forums as well. Not sure why, just didn't feel like it for some time.