I probably should've looked this up before I decided to comment but at least according to this:

https://commonvoice.mozilla.org/en/datasets

The ratio of male to female tagged voices in the English dataset is 45 percent male to 15 percent female. (The remaining 40 percent is untagged.) Odds are good that the ratio is closer to 75 25 than 50 50, at least by hours of recorded audio.