That's one hypothesis. Another equally valid hypothesis is that those that were published were just lucky enough to send their manuscripts to agents and publishers that don't have a bias.
A corollary to your hypothesis is that there are publishers and agents out there with the same "correct injustice" mindset that are publishing women just because they are women. How do I know this isn't the case?
Unless you have some objective measure of quality to measure books, you're just spouting bullshit conclusions that conform to your beliefs. Nothing more. Nothing less.
Might I suggest that you try the null hypothesis?
https://byrslf.co/the-null-hypothesis-loves-you-and-wants-yo...
FWIW, the essay I linked to was written by a woman. By your logic, you're morally obligated to read it.