High School Reunion

I went to my 5 year high school reunion today. While I was there, I figured out why my friendships have shifted since then. The people that I was close with in high school I am no longer close with, and people who I was friends with but not superclose with I'm much closer to now. This is because the ones I used to be friends with have no intellectual curiosity. They are content with the knowledge they have and have no desire to learn more. I don't understand that.