Not necessarily. It's like that thing about if Bill Gates walked into a room everyone's average net worth will go up even though their actual net worth didn't go up. If you had five people with 2 dollars and one guy with 14, the average would be (14 + 2 * 5) / 6 = 4. The average is four, yet everybody but one is below average. That relies on massive statistical outliers though, which you're not going to see when talking IQ. If you're talking about the median IQ, then yes, by definition 50% would be higher and 50% would be lower.
And by human choices I mean making choices that are essentially human nature. If your critical thinking skills haven't been trained and someone is purposely targeting what you already believe to be true for propaganda, I don't think that has anything to do with being smart or dumb. I also don't understand the importance of labeling it as such.