Hakatan- I agree with you that saying women need or must learn Gemara because they are exposed to and excel in secular knowledge is weak. BUT, their exposure and success in secular knowledge may create a desire to learn Torah at even deeper and more intellectual levels. That desire makes sense… If you’re spending so much time expanding your knowledge in the secular world, al achas kama vekama they may want to match it or even exceed that with Torah knowledge.
Now if it’s prohibited, then too bad so sad… Not much we can do about it. But is it prohibited? Hard to say that it’s prohibited when both the Rambam and Shulchan Aruch say that they are rewarded for doing so. I mean there are other examples of Torah mitzvos that the chachanim said not to do… Like blowing shofar on RH or shaking arba minim on Sukkos when they fall on Shabbos. But Chazal said no, so we don’t. Does the Rambam or SA tell us we would receive reward for violating Chazal to be mekayem the mitzvah doraysa? If course not!
So the very fact that the Rambam and SA open up hilchos Talmud Torah for women that they receive reward for doing so is pretty strong evidence that it’s not prohibited. (And then you just have to reconcile that halacha with the command not to teach your daughter Torah… Maybe that’s specifically a father, or maybe it’s imposing Gemara on women with a required class in school)
But, if they are genuine about learning Torah and engaging in an area of avodas HaShem that they are not obligated in, and it makes why this desire is more prevalent in modern times, then it’s a beautiful thing for then to learn any area of Torah they want, and they do receive reward for it!