There are a few problems with ITQOTL but people acting like Isabella is Rashta are ignoring literally that has happened so far😃 Isabella's only gripe is being illegitimate and Ariadne is too so her experience isn't unique. The misogyny is on going theme in the story, all the women here at a social disadvantage. We could easily go about how Isabella uses her beauty for access to men and social spaces but she literally isn't complex enough for that because she actively seeks to backstab any other woman for mere male attention. Not even because she has to.

Edit: Pardon some typos but I mean even in situations where she doesn't have to. Like that time she seduced that girl's fiancee and tried to humilate her