I wouldn't have had an issue if Xander was making snarky comments more based around Cordelia being a mean person, or even snarking on her being rich and spoiled. There were plenty of much more effective ways to insult Cordelia when they were going for one another, but he so often went for slut-shaming comments on how she dresses like a hooker or locker room talk is that she's mass transportation, and IMO that said far more about Xander than it ever did about Cordy. Although I do agree that his behaviour toward Anya was much worse, I always got the feeling that his dismissness of her was very much based on learned behaviour from his parents marriage, although even then the show only ever called him out on that once in DMP after years of him belittling Anya in front of his friends and treating her as lesser