The optimistic approach to those questions: we all became more intelligent. So the Gauss middleground now contains more people than 80 years ago.
"It garnered this attention for its intriguing yet simultaneously obvious finding: over the past 80 years, as a far greater proportion of North Americans attended college, the average IQ of college undergraduates dropped from around 120 to 102, just slightly above the average of 100."
https://www.zerohedge.com/political/x-users-didnt-papers-tone-and-findings-so-they-got-it-rejected
Discussion
We all did become more intelligent, but not necessarily more knowledgeable.
The question, of course, is if the scores were meaned to the same year, so that they could even be compared. I'm assuming that they are, which would mean that it's not because of an overall increase in intelligence.
Of course, we can't look at the paper to check, now, cuz it got censored. 🙄
