Sure, with a patriarchal system already in place, and women, all of a sudden, becoming 30% more massive, stronger, and [possibly] more aggressive, there’s going to be conflict. Although 1 on 1 male-spurred abuse toward women will now favor female dominance (assuming no use of weapons), patriarchal norms will linger until, and unless women revolt (e.g. civil war between the sexes, coup d’état, or friendly takeover). IRL, social change is rarely so binary or violent; it typically involves a complex interplay of factors, negotiations, and adaptations over time. Gender roles and power dynamics are influenced by a multitude of factors beyond physical abilities, such as cultural beliefs, economic structures, and historical contexts. But, this is one possible pathway.
If, on the other hand, women became 30% bigger, stronger, and more aggressive before the patriarchal society evolved, then I believe a matriarchal society would have instead developed. It would be realized that women are the better hunters and protectors of the pack. Of course, women would remain the child-bearers, but that would be accounted for. Women’s role may be that of child-bearer, hunter, and protector, while men’s roles may be that of child rearer, domestic chore doer, and temporary hunter (while women are in late stages of pregnancy).
This is highly speculative, for sure. One must consider the interplay of biological, social, cultural, and historical factors in shaping human societies, and it’s important to recognize that societal change is complex and multifaceted, often involving adaptations and negotiations among various groups over time.
Personally, I’d like to live in a society where the size differential between sexes is about the same as that of the Black Widow spider (~2/1)…but only if I could be born female.