it guess the norm is just to treat women as a means to forge a political alliance, rather than training them to take advantage of their softer form of power. Sansa was taught to be an uncontroversial housewife basically, which might be all that is expected of women typically. Honestly that might have been enough if Joff wasn’t Joff. Women’s ambition isn’t often validated or encouraged i suppose in westeros. It could even be said to be a weakness of their patriarchal society that they don’t validate women in this way. Which harmed both Sansa and Cersei in different ways.