To understand privilege, think of yourself as a D&D character in an incredibly poorly balanced version of D&D (let’s say 2nd edition). You have a gender, you have a race, you have a class, and you have an alignment. These things generally dictate how the game goes for you. Sure, there’s a luck element–roll that d20–but even that is heavily informed by your ability scores, skills, training, feats, etc. The result of your build is a map of your particular privilege (which varies widely for each PC).
But let’s look at a specific example:
You’re a lawful good paladin, I’m a neutral evil assassin.
When we’re traveling in goodly lands, or in the court of a good King or Queen, you–as a LG paladin–can expect good treatment, politeness, and the ability to follow at least most of the laws without compromising your values or goals. Maybe you even get some reaction bonuses to charisma checks and such.
That’s paladin privilege.
For me, however, as a NE assassin, I can’t follow my nature. I can’t do my job or employ my skills, under penalty of arrest, attack, or exile. In fact, my own party (you’re a paladin after all) is always bugging me to change my ways, and that it’s really all my own fault that people distrust or dislike me. If I’d just act more like you (maybe not dress all in black leather, maybe not stab the people I want but only the people society approves of being stabbed) maybe people would hate me marginally less.
That’s assassin privilege. And in most cases, it sucks. It is mechanically inferior to paladin privilege.
Are there some areas where assassin privilege trumps paladin privilege? Sure, but they’re rare. If we’re captive of a former or current employer, maybe I can pull some strings and get us not executed. You know, assuming you don’t say something insensitive to the dark lord’s philosophy and make us roll initiative.
But can you really blame me if I hesitate to use my assassin’s privilege to benefit the paladin who’s made my life miserable for multiple adventures?
Let’s go further to say you’re a human paladin and I’m a half-orc barbarian. When we’re in human lands, even if they aren’t necessarily goodly (maybe they’re neutral or even evil), you’re still going to be treated better because you’re a human, whereas I’m a half-orc (with an implicitly tragic backstory). This is human privilege (useful 90% of the time) vs. orc privilege (useful 10% of the time).
Elves are generally considered one of the best races, and they have pretty high privilege. Of course, they aren’t the best all the time–particularly if you’re playing an edition where elves get a constitution penalty. Fortunately, in D&D, you have that choice about what racial privilege you want for your character–in real life, you’re not so fortunate.
What about gender? Say you’re a male human paladin and I’m a female half-orc assassin. If we enter a realm where all the kings throughout history, most if not all of the lords are male, all the laws are made by men, men are in charge of the majority of the households, the majority of the guards are men, etc., etc., hazard a guess for me as to which of us will be automatically respected and which will be treated with suspicion. Say we’re both human paladins, in fact–which one of us will the guards in this male-dominated culture probably assume is the leader of our party?
(Though if we head into matriarchal Menzoberranzan, a female character would obviously have the advantage there.)
Heck, what about campaigns set in settings that have no non-straight people, or where anything other than heterosexuality causes waves of loathing?
Some classes have, historically, just been better than others: that’s privilege. Paladin privilege has been pretty constant across the editions, and wizard privilege tends to kick in around level 6 or so. Thieves and druids were pretty low on the privilege ladder until 3e showed up. PCs who utilize class enhancement books (Complete Arcane, Martial Power, etc.) benefit from power-creep privilege. Balance was king in 4e, with some exceptions (how about that Whitewell Warlock, huh? And who would willingly play a Seeker?).
Both in the game and in real life, there are hundreds of variants of privilege, all of which apply in a varying number of situations. No sort of privilege is an advantage in every situation, but some are generally better than others–if you’re lucky enough to have a privilege which is an advantage in 90% of situations, you’re pretty much set.
For instance, if you are sex: male, gender: cis-heterosexual, race: white, class: middle or above, alignment: Christian, background: American, then you can probably handle most encounters that you’ll ever have without a lot of effort (easy mode). The more you vary from that pinnacle of privilege, the more often you’re going to have to expend your powers and hope for some lucky rolls, and you’re going to lose more hit points than your paladin fellows.