Sorry for the derailment here, but, this just bugs me. H&W, how sure are you of your definitions? At least in teaching there is a difference between simulation and role play. In simulation, you are yourself in a given situation, in role play, you are pretending to be someone else in a situation.
I'm not sure where you derive your definitions, but, they are not the way those terms are used in teaching circles. And this might go a long way towards why you have trouble getting people to accept your position. Role play games are about role play, not simulation.
Anything in the last 30-35 years wouldn't define role playing as I mentioned. It is from the era of when role playing was largely picked up under a different understanding after WWII until the start of drama therapy in the 70s. Role theory in sociology was largely discredited (i.e. unpopular) at that time, but I have done enough reading on the subject to understand how the term had been used. Yes, in the 80's it became widely understood that role playing was the performance of a character as persona was merged into characterization and specialized uses persisted only in academic circles.
The history of role playing began with the work of Jacob Moreno in the 20's and 30's, which later lead to trouble in the 60s with sexual role play, then to the subsequent addition of elements like safety words because of that, and are still historically understood as the nascent beginning of both the term and the practice. The idea of role playing split and was largely supplanted during WWII to become more of a role training exercise akin to simulation as it was used by the German military and the practice became a director-led event (the origin of the GM). The American military noticed the profound growth in strategic battle field expertise in the German underage officers commanding troops near the end of the war. They took much of the practice back to the states where it lead to the common practice of military simulations for troop and officer training here and then around the world. In the 50s the practice became a "business phenomenon" as it became a popular technique for management training and educators picked it up en masse as the practice boomed. All of this changed in the late 70's with the common culture learning of and largely accepting postmodern theories coming from the universities and leading to our dramaturgical-based culture today.
If you know about postmodernism, then you probably understand that it contains, if not a rejection of, a dissolving of the practice of describing and understanding the world through pattern recognition. As Moreno had designed his theories like many sociologists of his time upon pattern recognition and posited role playing as a "third mode of being" it became somewhat taboo and an embarrassment to talk of role playing as anything other than theater after the late 70s. (This is also when the idea of the self as an endless series of masks became en vogue.) Philosophically speaking, the manner by which we engage with the world "out there" as an ongoing comprehension of an ordered universe goes all the way back to the Pre-Socratics Heraclitus and Parmenides. Like Kant would centuries later, Socrates (and his students) attempted to merge these two absolute positions (i.e. absolute eternal or absolute change) and formed much of western civilization's past including much of our current day language and phrasing. When this was set aside for a more literary and artistic founded society some of the practices of the past began to appear rather peculiar - like role playing.
How does all of this pertain to us and D&D? Well, if you think about it, why would anyone need 1000s of books with 1000s of rules to create a completely improvised story with other people? Today's answer is, "we don't." But it also quietly leaves it at that. It has been understood by many that the hobby of role playing games (and RPGs on computers) were persisting in an understanding of a practice which was no longer held as true - well, at least not worth speaking as if it were true. Games, especially abstract games, but also puzzles, still base almost every single mechanic they use upon pattern recognition - the ability to remember and recall what we previously experienced. Place that pattern in a sequence and expectation grows like it does when listening to music with tempo, melody, or rhythm. When postmodernism came out games (and music) were mainly passed over as people attempting to "feel the beat" or find the same card in the game Memory were not pursuing a religious growth of the "one true script(ure)".
I believe what past players may remember is the uncanny ability of DMs to provide an expected result without any communication on their part to encourage it. In other words, after many, many sessions we may come to a point where every player is expecting the DM to say "dog" due to a long ago "realization" of the game world. But of course the DM doesn't day "dog", he says "dog", because it is impossible to repeat or mean the same thing twice. The delusion stems from the same source by which many believe "communicating" by attempting to use patterns (in speech, text, etc.) enable us to understand others more or better.
Now why people still play with computer programs and treat them as puzzles rather than palettes to create a story is explained as naive realism. We think we can comprehend the world around us and live pragmatically doing so. When someone expresses an imagined world we express our desires into and we receive extraordinarily coherent responses in return, we tend to treat it pragmatically, like a comprehensible puzzle. That the person behind the screen is free willed and could say anything is why this is a game of theatre and pretend. We know they could say anything, but we build up our expectations anyways.
So yeah, role playing and role playing games were for a long time about simulation. It just took our hobby until the last decade to forget enough about why we've been doing it this way for so long and for postmodern theorists to describe another way. That it is probably hard to find out about this stuff is due to many factors, partly from our current cultural acceptances, but also due to the shame many feel about it, and practices like puzzles and their sales shrinking to only subgroups of mostly cultural conservatives (of which I am not one).
Well, that hit on philosophy, religion, politics, and probably godwinning, but I think it's all pertinent to your answer. Ironically, it's all very much about the roots of RPGs and D&D.