That's interesting -- I didn't know about that. However, it's only hypocrisy if Johnson had made a big deal out of "family values" or traditional morality. Although I cannot claim to have read all of his work, my impression is that he largely concentrates on "big picture" conservative issues, dealing in power, liberty, and the struggle of democracy with totalitarianism. I never thought of him as a "social conservative."
Well, he attacks Marx for having a "sex slave" in his basement, and overall his message is that you can't trust these peoples' views because their personal lives were hypocritical.