It is not just the taboo. The sterotypes are less and less accurate, and less and less about matters that folks care about anymore, to the extent it still has any accuracy at all.
Certainly they did have a common language and common cultural references which their parents and grandparents didn't have, but it could be difficult even so. For many people in those days it was very much a matter of not saying things that came readily to mind, and that's something Nixon had trouble with.
Nixon wanted to be a regular guy. And he most definitely wasn't one. He had real intellectual gifts and was a very studious, hardworking fellow who had no small talk and was ill at ease with other people. Maybe he first really "belonged" when he was in the Navy, a regular guy among others. And in politics it didn't pay to be an aloof egghead, like Adlai Stevenson, so Nixon cultivated the common touch and tried to be an ordinary Joe, even a tough guy.
Of course it didn't work. It's better for a politician to have the people skills mastered first and procede from there. If you don't, you're probably moving in the wrong direction, following where you think the people are rather than leading them, trying to build a personality when that ought to be something you start out with. And if you really have to work hard to establish a rapport with people, chances are you get things wrong, as Nixon so often did.
I tried to read Lance Morrow's book, "The Best Year of Their Lives: Kennedy, Johnson, and Nixon in 1948: Learning the Secrets of Power." It was awful! Rather than simply stick to what happened, Morrow embellishes his story with Freudian insights and pop culture analogies. The comparisons of Nixon to Lana Turner and the Hiss case to "Streetcar Named Desire" were bizarre and laughable. I did get the impression, though, that Nixon's was the most compelling of the three lives, and Kennedy's the least.