Any sports? Leadership?
Princeton may be shifting more conservative this year. One of the more common themes among some interview candidates who have contacted me for advice is that they have prior full-time work experience. Given your profile, I am also a little surprised that you havn't received an interview offer. However, you are an international applicant, even if from a school like Oxford, Cambridge, LSE or Manchester. And you're probably up against the salutatorian from Ecole Polytechnique where there are ~10 seats and perhaps 25 interview slots for all of the European applicants.
I can't explain a potential ding between you vs the other applicant from your school. Sometimes it can be random and you can't take these decisions as an up or down vote on you vs someone else. I do know that if I had applied as a European undergrad, I would have gotten dinged.
I can certainly empathize with a potential ding. In high school/ secondary school, I was known as the brainiac who got a perfect score on the SATs and was heavily involved in Boy Scouts and on the Swim Team. But I got rejected from Princeton while other students from my high school got in. Watching other kids that I didn't think were smarter or harder working than me traipse off to ivy league schools while I went in-state was a tough experience. (To be fair, I also didn't have the money for a private school.) But in the end, it didn't matter. When I graduated, I wound up in the same place as them, with $100K less in debt. It will likely be the same for you.
But I'm not sure they're done handing out interview invites yet, either. So as much as I want to offer folks comfort on this, I'm not sure anyone's been dinged yet. My hunch is that five people are going to show up next week saying they got interview invites, and one of them will be someone who posted on quantnet thinking they got dinged unfairly.