Maybe I misunderstood the point of your comment but I'm not trying to argue that reading is good for you (which I personally believe), just that it isn't bad for you and I'm not aware of any controversy around that latter point as I have never heard anyone argue that they are bad for you and I couldn't find any studies saying that it is bad for you. If you think that point is controversial I'm willing to entertain the argument but the claim doesn't seem that serious to me.