I think you may have misunderstood the message: I think he is warning (as some psychologists like to stress) that causing discrepancies in one's world view can be very stressful and painful, and that showing facts may not be productive and effective with some people¹ - so he is warning about awareness for politeness and effectiveness.
¹(to the arm-tossing author of the article, seemingly (indiscriminately) you, janto, and your unknown neighbour - and you would be right in protesting against him for the insinuation)