The premise of this study looked intuitively unlikely to me. However, I really like intuitively unlikely premises that turn out to be true, so this was right up my alley.
It turns out it's not unlikely. It's just lunatic. Notice the words "can," "might," and "could" in the description. They have mathematical models that show that if women had started out being the warmakers somewhere, this would have been reinforcing over time, and their sex would be the warmaking one now. It hasn't actually happened anywhere, so perhaps it wasn't quite a coin flip. One would have to go back farther and farther into our evolutionary history - past the first primate, perhaps - to get to coulda-been-this-coulda-been-that situation. It gives an excellent expression to the old saw "If my aunt had balls she would be my uncle."
You will continue to hear a lot about the spotted hyena, where the females are more aggressive, because it provides an exception. It will be held aloft, not as evidence that one-off situations under special circumstances are always possible, but that we are mostly quite malleable and can be changed to other behaviors (if we just pass the right legislation, maybe). It is similar to finding the language in the Caucasus in which "Dada" is used for mother, showing that "mama" cannot be a shared word from the first language; or the few primitive societies that are matriarchal proving that humans were equally likely to develop that way but for the merest chance, and we can change it back whenever we like.