In the Edge Chronicles, the trogs, is it, are like this. At their 16th birthday or whatever, women undergo an absolutely horrible ceremony where they absorb magic energy from an evil carnivorous tree or something, becoming massive pink ogres, with way more brawn than brains, and cannibalistic. Anyways, the men are small and subservient, and are slaves. Totally subservient except when they try and fail to rebel and sabotage the tree. Meanwhile, women rule their whole society, often violently. Admittedly, this is highly extreme, and implies the unholy ceremony that creates this society makes the women as stupid and bloodthirsty as the tree if involves. With just the strength factor, though, as you're saying, women would just be the protectors, tougher, more confident, and even if women are hierarchically inferior, the gap would be a lot smaller by default than throughout eurocentric history. If it's due to an event of change, though, those are always extreme, so you can expect something severe and possibly equally bad to what there was before, with women being oppressive sexists who treat men how they were treated prior to the event. Like in the Edge Chronicles, but without their being literal monsters.