> I think SAT/ACT are bad indicators for the "elite" schools because they just saturate

this is a feature. Elite schools don't want to be able to tell the 0.5% from the 5%, because then they wouldn't be able to select for rich and solidly but not amazingly competent kids. They'll take the 0.01% olympiad medalists to fill their genius quota, then fill the rest of their cohort with solid, hardworking, well-connected kids who'll boost the prestige (and donations) of their institution more than the scrappy smart kid who aced every standardized exam with no support to speak of but probably won't (want to) learn the lingo and do the hustle to make it into McKinsey's.