Honestly. this is the first time I've seen people speak up about sexism/racism. I don't know whether people have been voicing their concerns through PMs, but publicly this is a first I personally see (or maybe I just don't lurk enough). If people have been having problems with some of the users content, the issue should have been brought up, the 2nd or 3rd time it occurs, and should have been dealt with.
To make this place better regarding sexism, I urge females to voice out any concerns the moment they see it. You can pm a friend/admin, etc, but make sure your voices are heard. In general, I think it might be a good idea to have a feedback admin (or system), someone who takes in all claims of inappropriate content and reports them to the rest of the mods.