Or perhaps because it forces the reader's mind to move away from the obvious, most of whom tend to be male.
I would prefer to simply see a few more female names in 'normal' lists, as splitting lists by gender does have the effect of making you think along the lines of 'if it didn't specify that they have to be female, would any of these women be taken into consideration?' (Probably only a couple of household names would.) There have historically been fewer female bass players around, so, proportionally, there will have been fewer outstanding female bassists than male bassists. I don't think all-female lists are the solution, though.