AN AESTHETICAL THEORY OF MMORPG GAMING.
I. Who is the first MMORPG player?
WARNING: there is no tl;dr since it makes no sense for it to exist. It makes no sense for it to exist because the answer to the question posed makes no sense either and cannot be sensibly (mis)understood without going through the senseless skein of digressions here bewritten. Like a skein too, that answer will be prone to fly off of the reader's mind. You have been warned.
See, we believe the answer to this question to be an easy one: people will point to a game like Meridian 59  (without acknowledging there were games that actually had all necessary characteristics to make them an MMORPG before it  ) and common sense will say the first person ever to play that game (whichever we decide to be the first MMORPG) is the first one.
The first player to play a game is the first one to play it.
Of course, but that “first” in my question is not about who was first in time, but who is the essential, the primordial player.
Who or what is the archetype of an MMORPG player?
Since I am here to ruffle feathers, undo wrongs and do damsels... I mean, save damsels in distress, I will first briefly explain how literary works and video games are related. I'll do this because our archetype is neither a gamer nor someone related to video games: it's a character in a book.
Most people nowadays think, or believe, or believe they think that when playing a video game one experiences a story by somehow shaping it, while reading a book is a passive hobby where one simply observes what the author wants him to observe without any kind of influx on its development. But in literary works this is far from the truth. Sure, one does not physically participate in the narrative, but instead places a lot of aesthetic judgements upon it; those judgements shape intentions, bring us closer to plots and characters, and configure purposes the author decided not to disclose in the writing process. We recognize ourselves in protagonists or perceive them as our opposites. We make decisions too: in The Trial  it's you the one who decides if K is explaining objective facts or just talking a lot of BS. We wonder about the past and the future of not only people, but whole universes (how it must have felt to participate in the War of the First Men and the Children of the Forest?).
Those kind of things are what we bring into the act of reading. It's not a hands-off endeavour at all. In fact I think that novels and video games are so alike that the only differences are A) The physical act of pressing buttons to make a character turn right instead of left, and B) that the persona we identify ourselves with inside a game is always the main character. Still, there is no video game where one can actually create a story, not even sandbox games can do it: the plot is as pre-programmed and pre-established as the one in a book. There will never be one.
MMORPGs are special in that they offer us (at least some of them try to) complete virtual worlds where we can "live" in through our avatars. We do the same things we do when reading a book: wonder, participate, judge, like and dislike, etc., but what defines us is that we become the focal point of a story beyond the main story. You are not Aragorn, but perhaps you are Elfhelm or a nameless (from the main story's point of view) man who died in battle. We interact with a world (a virtual one) by pretending to be someone else, by playing a character.
Where have I read about someone else doing this exact same thing a long time before MMORPGS, video games, computers or even RPGs existed?
That's right: in the founding novel, the primeval tale of tales: Don Quixote of La Mancha.
Let's see how.
We are told at the very beginning of Don Quixote that our Knight is crazed by reading books of chivalry and off we go following him out and about doing crazy things in the fields of La Mancha. He is a madman trying to be a Knight-errant (a.k.a. a madman doing idiotic stuff). Is he really?
Check this bit:
To this the peasant answered, "Senor--sinner that I am!--cannot your
worship see that I am not Don Rodrigo de Narvaez nor the Marquis of
Mantua, but Pedro Alonso your neighbour, and that your worship is neither
Baldwin nor Abindarraez, but the worthy gentleman Senor Quixada?"
"I know who I am," replied Don Quixote, "and I know that I may be not
only those I have named, but all the Twelve Peers of France and even all
the Nine Worthies, since my achievements surpass all that they have done
all together and each of them on his own account." 
Ah, he is not completely mad because he knows who he is, he's only mad north-north-west. When have you ever seen a madman knowing who he really is? A madman, a crazed person thinks that what he believes he is, he is for real. But the Don knows the distinction between his true self and his character when confronted about not being the Don. So he's not really crazy.
Is he playing a game? Is he acting?
We can answer affirmatively: Yes, Don Quixote is playing a game, he is pretending to be a fool. The same way we pretend we are in that virtual world killing dragons and travelling through enchanted forests.
If he knows he is not the Don but still chooses to act as being it, is he the crazy one or are the people who believe he is really the Don (e.g. his squire Sancho) the crazy ones? He plays a role and knows he's playing it. There are some folks in the book that think Don Quixote is demented but still treat him like a real Knight, they are playing a role without knowing they are playing it, isn't that bonkers? I mean, if you go to a mental hospital and this lad tells you he's Napoleon, would you seriously say “I'll fetch Josephine for you, my Commander”? You could play along of course and say it, but there's no chance in hell you would run to the airport in order to catch a plane to Paris and go look for her. Still, here there are deranged lads (e.g. the barber, the priest) who until the very end urge our Knight to continue his quests, even participating in them, all while thinking he is the insane one. Talk about idiocy.
Quixote is the sanest person in the whole story.
By the way, he is also genuine: he treats people as they deserve to be treated, not as how society treats them. In the first part of the novel he arrives to an inn and is greeted by two women (prostitutes) who help him relieve his armour, because of this he sees them as fair maidens and behaves accordingly . In the second part he is received in a castle by a Duke and a Duchess who scorn him. Our hero outraged treats them with contempt and defiance . Quid pro quo Clarice.
But, if he is genuine how can he be pretending? If he was pretending to be a genuine person, he would then behave like the barber, the priest and Sancho would, he would be them. But in his so-called “madness” Don Quixote behaves in the exact opposite way.
What I think might have happened (in those bits and during most of the novel) is that Quixote is really - objectively - angry because they are making fun of his pretensions. Alonso Quixano "The Man" is mad because they make fun of Don Quixote.
I have no idea why critics and readers pitch Don Quixote against Sancho when explaining the novel's portrayal of Idealism vs. Realism. While we have seen that in fact Don Quixote is an idealist, Sancho is anything but a realist: he does not follow fact or experience in order to make sense of his world, not even the most immediate experience given by his senses; he does not believe the world persists when he's not watching, he changes his beliefs on the fly, his world-view is grounded on mere circumstances– Don Quixote is wearing a helmet which he swears is the Golden Helmet of Mambrino, the barber says it's a basin (you know, a bowl), Sancho says it's a “helmet-basin”, a “helmasin”. “WTF dude” says Don Quixote, “you are lying not just one, but a thousand times!” 
Who do we behave like when we play video games, especially when playing MMORPGs (these supposedly immersive experiences)?
We all want to believe we behave like the Don, which is impossible since we have no means of pretending we are part of the game, know we are pretending it and be genuine, all at the same time. It's just not possible.
Don Quixote does all those things simultaneously and we are unable to understand how he pulls it off: he is infinitely more clever than us.
We as gamers behave like Sancho. He is a distilled description of what we gamers are, his architecture is ours, he's the blueprint of the fool circumstantialist we all are.
This is not bad at all. If Sancho has a redeeming quality is that of being the bridge that joins Quixote's world with the world inhabited by the barber, the priest, the Duke and Duchess, the two prostitutes and everyone else. All of them are so dull, so self-involved that are unable to see past appearances: their world is a pre-fabricated one they accept only because it's accepted by others. They do not pretend, and yet are unable to be genuine.
The faithful squire is the critical transition between two cosmoses. Tired of watching shadows in a cave, we call the first step we took into reality “Sancho”. The more we submerge ourselves into the story the more we see Sancho grow and become like his master. Sometimes he pretends and he knows he's pretending; other times he's truly genuine (although still a simpleton) and then he cannot but embrace his disbelief. The more we read the more he learns the more we learn.
We, like Sancho before us, grow and learn by acting in a world displayed in front of our eyes. Sometimes we feel connected to our virtual avatar and care for him, we pretend we recognize ourselves as part of that world and genuinely act on it, but then we must forget we are pretending: we become Role-Players. Some other times we pretend we are part of the world and recognize we are pretending, but that impedes us to act sincerely inside the game: we are gamers.
To do the three is reserved only for Don Quixote, that magnificent Homo Ludens we all aspire to be.
(5). Don Quixote of La Mancha. Part I, Chapter V: http://www.literaturecollection.com/a/cervantes/don-quixote/7/
(6). Don Quixote of La Mancha. Part I, Chapter II: http://www.literaturecollection.com/a/cervantes/don-quixote/4/
(7). Don Quixote of La Mancha. Part II, Chapter XXX: http://www.literaturecollection.com/a/cervantes/don-quixote/86/
(8). Don Quixote de La Mancha. Part I, Chapter XLV: http://www.literaturecollection.com/a/cervantes/don-quixote/47/