The Stanford & Harvard's of the world have a very real interest in ensuring that their demographics are preserved. "Well rounded" is a cop out, and your anecdot

The Stanford & Harvard's of the world have a very real interest in ensuring that their demographics are preserved. "Well rounded" is a cop out, and your anecdote is a false dichotomy. The high achieving students you're describing aren't not participating in extra curricular activities. That just sounds bizarre. Anyone who's intensely focused on getting into a top school also has their application filled with extra curricular engagements.