Sam Harris is actually likely a Ti-ENTp. He has made statements that fall into the causal-determinist mindset, like not believing in free will (summary) since in CD terms everything falls into a long chains of cause-effect interactions which doesn't leave much room for freedom of choice. Gulenko prescribed CD style of thinking to types like LSI and ILE but not INTjs. Even so that would still put them in same quadrant, so the source of their disconnect is probably not their socionics types. One thing that may be contributing is that they likely have opposite instinct stackings, which could lead to scenarios of people talking past each other and having a difficult time getting a grasp on what the other is saying.