I'm not sure where you obtained that number from, but from my experience I don't think there's anything particularly remarkable about the natural intelligence of a typical university student. Then again I score in the 99th percentile on most standardized tests I've ever taken so my standards might be warped.
University admissions doesn't select for intelligence. There are retards who manage to attend prestigious schools for no other reason than the fact that their parents attended the same school. Or that they're tall and can throw a ball really far. Or they happen to be part of a favored demographic. Then there are those in the upper-middle-class who are of average or slightly-above-average intelligence, but they can afford private schools with significantly smaller class sizes and where guidance counselors regularly wine-and-dine university admissions officers. There are reasons why high schools like Andover and Deerfield in the U.S., or Eton and Harrow in the U.K., or Le Rosey in Switzerland can cost upwards of 65k USD a year.
And even university courses don't select for intelligence. Grade inflation is rampant, particularly in the social sciences. Everyone gets an A or A-. Ideological bias is rampant, particularly in the social sciences. If you agree with the professor, you get an A. And most universities will not admit to this, but cheating is rampant at the undergraduate level. University students regularly collaborate with each other on take-home assessments where they are told not to do so. I guarantee it. And anti-plagiarism software can't detect instances of contract cheating, where students pay someone else to do their homework for them.
There are, I suppose, particular university courses or programmes that ruthlessly select for natural intelligence and/or memorization skills, such as Math 55 at Harvard, but they are the exception, not the rule. Maybe it was true 20 or 30 years ago that simply having a degree was an indicator of above-average intelligence, but I'm confident that that's no longer the case.