It's much easier to have a great selection of feminist books than a great selection of books...good luck competing with the internet in the 2nd category.
There was a documentary about specialist stores popping up in Berlin, and generalist stores dying.
I would confirm this as a resident of the aforementioned city.
The specialist (or even many generalist) bookstores usually follow a certain ideology and sell books heavily aligned with those views. Unfortunately, this slowly converts those stores to echo chambers as the objectiveness of the stores slowly fade away.
I used to live near an excellent technical book store which carried things like O'Reilly books. It went under as the Internet progressed. Many countries have such things like math book stores, or stores specializing in philosophy and similar humanities.
Specialized book stores have a long, reputable history, and the echo chamber style specialization is a pretty recent phenomenon.
Go to Boulder Colorado. It's so easy to spot sexism against men all over the place, including feminist bookstores that are there to make money off the rich bored people "culture wars".
I suspect that neither majority of men nor women are interested in feminist literature per se. Unless "feminist" mean "written by women" and not "in the spirit of feminist movement".
Probably similar to the NYT subscriptions surge during the Trump administration. People just buying to signal and "support the cause". Partisan views have it a lot easier to raise money from their followers than those trying to find a middleground.
