As someone who's interested in writing, I have noticed things changing over the last few decades so I was interested in the how the situation has evolved over time based on data. I dug this up:
There seems to have been an inflection point in the 1990s, which the author posits is due to the rise of MFA degrees (2/3rds granted to women). Commercially, the gender ratio seems to have approached parity overall, even if in specific categories the large imbalances exists (owing to various factors, some self-selection effect exists). Even though commercial success seems to be at parity, the author posits that the publishing industry lags behind in reflecting this and that there remains a funnel bias in the industry (from critics to publishers).
Bias, She Wrote: The Gender Balance of The New York Times Best Seller list https://pudding.cool/2017/06/best-sellers/
There seems to have been an inflection point in the 1990s, which the author posits is due to the rise of MFA degrees (2/3rds granted to women). Commercially, the gender ratio seems to have approached parity overall, even if in specific categories the large imbalances exists (owing to various factors, some self-selection effect exists). Even though commercial success seems to be at parity, the author posits that the publishing industry lags behind in reflecting this and that there remains a funnel bias in the industry (from critics to publishers).