Yes. There were many things about Nixon that were exaggerated, some by his supporters, some by his enemies, but this was not one of them. He was profoundly introverted and socially awkward, which as virtually all his biographers have mentioned, was an extremely odd trait for a POTUS to have and might have helped doom him during Watergate. It is extremely hard to envision, say, Ronald Reagan or Bill Clinton floundering like Nixon did in the same situation.

Among other stories:

• Nixon would often badger Haldeman to shorten state dinners and the like so that he could avoid talking to people more than necessary. He was throughly misanthropic. He even eliminated the soup course on the grounds that "real men don't like soup", in part because he was terrified of spilling it.

• Haldeman was essentially Nixon's "minder", taking care of the necessary social lubricants and organization skills for him. He was intimately familiar with his the quirks of his boss as few others were. When Nixon was overstimulated or in a foul mood, he would throw out orders that Haldeman (who, whatever his many faults, was a very sober, down-to-earth individual with no power ambitions of his own beyond what he had-so, he was perfect for this) deemed insane, overly vindictive, or politically unwise. Haldeman was expected to use wise discretion and know when to "sit on" an order until Nixon forgot about it or had reflected upon it in a more calm mood and retracted it. This worked for a while. Nixon's infamous order to burglarize the Brookings Institution was never carried out for a reason: Haldeman knew to let that one die, and after August of 1971, Nixon never brought it up again. However, Nixon would find enablers in more literal minded aides, and Haldeman was as guilty as anybody in contributing toward the paranoid, cut-throat atmosphere of the Nixon White House.

• Haldeman also got Nixon to do things he didn't want to do by applying gentle pressure when needed, and knew how to deal with the various mind games and "roller coaster" emotions. Needless to say, all this combined with the fact that he controlled access to Nixon gave Haldeman an immense amount of power within the administration, probably moreso than any Chief of Staff ever had or will have again. Haldeman's resignation was absolutely fatal to Nixon's ability to function in an office so at odds with his personality.

• Nixon insisted on having an hour or two alone each day to think, reflect, write down policy ideas on his yellow pads of paper, very much in contrast to modern Presidents, or executives in general, really. He was probably never more comfortable than during these times, not least because it provided him some respite where he could be alone with his thoughts. Nixon was fundamentally a man of writing and reading rather than speaking, and this tends to obscure historical studies of him. If one wants to actually understand Nixon's policies as opposed to his personal idiosyncracies, you have to look at the memorandum and other written material, not just the tapes.

• Nobody-with the sole exception of his wife, Pat-called him by his first name, even Bebe Rebozo. Formal in all regards. Wore a coat and tie even when home alone. Within the government, only a handful of men-Haldeman, Ehrlichman, Kissinger, initially Moynihan, later Colson, and J. Edgar Hoover before his death-had open access to Nixon. Anybody else had to go through Haldeman, the top leaders of the military, intelligence community, the cabinet, and Congress included. Polar opposite of his predecessor in this regard: whereas extroverted Johnson had a pathological desire to be loved and did everything he could to be "plugged in", the introverted Nixon never expected to be and wanted everything to do to minimize contact with humanity.

• Yep. Not only that, but Nixon mimicked basic social interactions, as well. He was good at it: good enough to actually be surprisingly magnetic in private, especially if talking about his all-consuming obsession with foreign policy. But it was always a script, not natural, and if you dig deep enough, it shows. Nixon simply did not have an intuitive understanding of how social interactions worked.

• Going off the above point, some of the more colorful Watergate tapes are very clearly products of Nixon trying to sound like... what he thought ruthless, macho tough guys of his generation were supposed to sound like. He's actually trying too hard to be something he clearly isn't while doing it. (To get what I mean, compare the Nixon tapes to, say, LBJ swearing. You can just tell the difference. Johnson is having fun, he's down to Earth, he's in his natural element, it is all in good humor and without mean spirit, no matter how crude it could get. Not Nixon.)

• Nixon's random, elliptical style of talking was also in part designed to reduce the possibility of conflict and rejection to an absolute minimum. You have to always remember this when hearing Nixon talk on the tapes: is he engaged in a maneuver or a ramble or a mind game?

• Nixon, like Eisenhower before him, was unable to disagree with anybody face-to-face, and he absolutely hated large meetings because of the potential conflicts they could rouse. Unlike Eisenhower, Nixon simply couldn't rely off of gravitas, though. So often, Nixon would engage in elaborate strategies and mind games to get around all of this: say, for example, knowing everybody's position going into an important mass meeting, pretending to agree with each individual staff member in private, and thereby identifying and isolating those he disagreed with at the conference table without face-to-face rejecting them.

• Nixon could be surprisingly open to criticism. He was actually probably among our more candid and realistic Presidents when it came to, say, what he did wrong during a speech when analyzing it afterwards, or whether he should have taken a different tack with a certain foreign leader. He even encouraged criticism from staffers... but only if it was written down on paper. Same for overriding decisions or contradicting his subordinates: always on paper. Never verbally. Verbal criticism, or a refusal to pander to Nixon's petty biases or mind games, was a sure way of getting frozen out. People in the Nixon White House learned this quickly and adapted. This had consequences during Watergate.

Sources:

Richard Reeves: Alone in the White House. Honestly, pretty much any Nixon biographer would do, as you can't really discuss Nixon without discussing his extreme introversion, but Reeves does it best.

HR Haldeman's White House Diaries, Henry Kissinger: White House Years/Years of Upheaval. Take them with a grain of salt, but these two men are probably the ones who spent more time with Nixon than anybody else in the administration. They are pretty candid about Nixon's highly introverted and often weird personality.