Why do men say stuff like "you wanted equal rights, you got them" when asked about things like chivalry?

I don't think ti is equal rights that has led to a decline in chivalry so much as women insisting that chivalrous gestures are insulting and demeaning to women, implying that women are weaker, more fragile etc. Women often react aggressively to male attempts at chivalry,and this naturally has a discouraging effect on men.