Personally?
I think (probably a lot of) women think that men prefer bald or nearly so because of men who use phrases such as "unkempt hairy bush." It's unkempt, btw, not unkept.
Basically, tons of men have super opinionated thoughts on women's pubic hair and are not afraid to shout it all over the internet and to anyone who will listen. And plenty think pubic hair is "gross" or "dirty." And lots of women internalize this and therefore will get rid of it just because some douchebag won't perform cunnilingus if there's any amount of hair.
Out of rebellion, I rock a 70s rainbow vag fro and no one can tell me it isn't SPECTACULAR.
Because I'll do whatever I want with my body hair. My body, my choice.