Yeah, Armstrong gave some lectures here and there, but basically he was very laconic and aseptic about the stuff, a very quiet man (and that fed a lot of speculations about his "silence"). The Apollo héroes were accused of being liars and members of a conspiracy, that's enough shit and possibly deserves only silence. Mitchell could seem some sort of over enthusiastic believer on ET reality, but he actually looks like a man talking about what he basically knows for sure.