<p>Of course the baseline of comparison matters, but two that I'm quite familiar with that have become much more competitive in terms of numbers of applications/acceptances in the last 10 years are UChicago and Reed. Both of those colleges were and remain rather self-selecting; the stats of enrolled kids were and remain well above average, even though the stats are also improving over time partly because the admissions offices are receiving much greater numbers of applications.</p>
<p>Taking a longer look back, Stanford wasn't really all that special through the post-WWII era and for a while beyond. With or without a correction for its change from about 55% white boys to maybe less than 25% white boys, it has certainly moved up the competitive ladder in fact and not just in application count since that era. Less so in more recent times.</p>