As virtually all established religions originated after the agrarian and before the industrial revolution, it does not come as much of a surprise that they reflect the moral and cultural norms of an era that revolved around land ownership, chains of succession, and the repression and controlling of female sexuality. Even Buddhism, which might look like a perfect candidate for a more egalitarian stance, was deeply enmeshed in sexual politics since day one, reflecting the mores of the society around it.
What we need to keep in mind in this context is that sexism - like racism - is first and foremost based on the assumption of a fundamental and essential difference between the postulated categories. "Jews are weak intellectuals, Africans are naive athletes." "Men cannot express feelings. Women are gushing with emotion."
This difference informs the sexists' perception of the world and their own place within it.
Now, the question is: can religions that are so deeply rooted in the past adapt to a new era - and do they even intend to do so? Since many of them regard their texts as timeless revelations, and since these texts are so fundamentally rooted in bygone ages, I wonder if a "transplant" is possible.