> The way to select them is to let the academic staff who will be teaching them decide. They will do that by means of exams and interview. How hard is that?
This debate is often framed as "Harvard vs MIT", where Harvard has been very successful in being ever more prestigious and important with their explicit "the smartest and the richest" strategy, while MIT is great, but not "near monopoly on the halls of power" great. The arbitrariness and thinly veiled racism of the admissions process is vexing, but they are crazy successful.
All that to say, it's not as easy as it seems it should be.