There are brilliant people from both private and public schools, but I’ve been surprised by the number of not especially intellectually talented students I’ve come across at “elite” US universities. So I tend to agree with Niall Ferguson:
“When I moved from teaching at Oxford to Harvard, I was puzzled. Based on my reading of midterm exam papers, a substantial proportion of my new students wouldn’t have got an interview at Oxford, never mind a place. It was explained to me that a substantial chunk of undergraduates were “legacies” — there because their parents were alumni, especially generous alumni — and another chunk were the beneficiaries of affirmative action or athletics programs.”