My kid was an average excellent student academically: 33 ACT and 3.9 UW GPA with many AP classes. No music or athletics. NMF. However, his admission officer who read his application and essays did tell us he thinks our kid would have gotten into other HYPS schools. I do think he’s good at planning ahead and doing just enough to get by. Must have been that his essays made him stand out for some reason.
But let me say this: I do strongly believe that if the adcom had to meet and interview each applicant, results would be significantly different.