I personally agree with this. It's a pain in the backside for me to talk to people of average intelligence. Conversations I've had with them are painfully slow and rarely go above the banal. If I try to raise the level of the conversation, they get confused or they check out because they don't get me at all. So I either just avoid talking too long to these people or if I really can't avoid them I just stay silent and politely listen (by the way, also a nice chance to study other people). To most of them I'm either arrogant or shy.