It turns out that regular male voice is on average an octave lower than a female voice, but men and women both "creak" at the exact same frequency. Not-so-tangentially, as a political science study points out, both men and women prefer political leaders with lower voices and associate lower-pitch with traits such as integrity, strength, and competence. So there's a very solid possibility that women are emulating masculinity voices as a way to consciously or unconsciously sound more like men for some perceived benefit. And in fact, according to Lexicon Valley, women who use the vocal fry are perceived as "contemporary upwardly-mobile young Americans." Since I like to think I fall into that category, and accordingly spend a lot of time with other people in that category, now that I've noticed it, I can't stop hearing the fry.
Hat tip: DW and COC