If facing others, Su Wenyue might need to rack her brains for solutions, but with Madam Wang's vulnerabilities laying bare, if she couldn't trample Madam Wang beneath her feet, Su Wenyue would despise her own intelligence.
Moreover, Madam Wang didn't seem to have much of a brain; otherwise, with a superior above, she would have had the sense to at least treat her prospective boss's wife with civility, understanding that the magistrate's power couldn't match that of her mother's family, a concept everyone grasped. Yet Madam Wang clearly did not. Perhaps out of dissatisfaction, she dealt with Su Wenyue as brutally as she would with her servant girls or concubines at home, actions that likely weren't instigated by Lord Wang who, for all his flaws, wasn't a fool in this regard.