Religious people and intelligence

Greetings from one of the least religious countries in the world, Estonia. I am interested in what is religious peoples thoughts about this. Various and different meta analysis have shown that on average, religious people have lower intelligence, they score lower on IQ tests and so on, than non religious people. What could be the reason? Is it the science-religion conflict overall, starting from the creation of the world and therefore less interest from religious people towards science? Could it be something else? PS. I dont mean to harm or insult any of you with that post, I am just curious on your thoughts about this.