I love the point Sam Harris makes in that video. No matter how smart or cultured you are and no matter how much of a blue blood you are or how regal you think your ancestors were, if you go back just 100 generations you'll see that they believed things that are appalling by current standards. It's humbling to think about, both in terms of where we came from and in terms of what our descendents may think about our beliefs today.
This reflects, to a degree, one of my viewpoints on the belief of God. I've stated several times that at one point certain civilizations thought that the Sun was Apollo riding his chariot across the sky. Later we found out that it actually wasn't. And lots and lots of other things that we attributed to some kind of God or another and took actions based on that.
I think religion makes sense to many because it's what we've heard from birth. But imagine if you never heard of any kind of concept of God at all. You are out of college and you've learned about evolution and our ancestors and the dinosaurs and the sun and moon, other galaxies, and everything else. Then, at 24-25 years old somebody said, "no, there's an invisible man in the sky that created everything". "This invisible man is controlling every aspect of your life and if you pray for things he will answer your prayers and provide for you". If it wasn't until that point in your life that you heard the story of the bible (or any other religion) after having already heard everything else. It would probably sound absolutely insane.
I will also say though, that it touches no another thought that I've held and that's that we are still very primitive. Way more primitive than we even realize.