One only need look at the source publication (a magazine of stories deemed “unheard” by a British oligarch). Skimming Wikipedia, this bit made me laugh: “a magazine publishing people who are generally unheard because people edge away from them at parties." Exactly the case here, except the author felt her oh so privileged voice was silenced because she wasn’t heard at a school boarding meeting…2800 miles away from where she lives. Also, if 70% of the school shares characteristics with you, maybe introducing some diversity isn’t the worst thing in the world.
Anecdotally, as a former internship director, I’ve taught many of the students from high schools named in these articles. Ultimately, every student is unique and needs to be considered on a case by case basis. But many of the students who struggle are those with helicopter parents like the author. Through early hard work and ambition they have book smarts or can study, but have never encountered any real setbacks and expect everything to just go their way, which obviously doesn’t happen in the real world. It’s those students who have to struggle, the one the author otherizes in her article and doesn’t want to see in the same school as her kids, that go the farthest.