Sorry, RC, but I'm pretty sure you're wrong about this.
Novels are a passive form of entertainment. You read, you absorb, but you don't contribute to the story. It's there, complete and intact, for you as for anyone else.
By contrast, RPGs are an active form of entertainment. You and your group together tell the story, and it contains what you collectively put into it. Whatever depth it has (or lack thereof) is there because of you.
Now, I do agree that some games can facilitate some types of play more easily than others. And it is certainly true that if I wanted to tell a "deep and meaningful" story, then I certainly wouldn't use a rules-heavy system (like 4e, 3e or Pathfinder) for that purpose. But that doesn't mean it simply can't be done.
I disagree that novels are a passive form of entertainment, although not that novels are
more passive than rpgs..... Certainly, I disagree that the reader doesn't contribute anything to the story.
I have read LotR over 30 times, for instance, and my perspective at various points in my life has certainly added to what I got out of it each of those times. Things I had largely glossed over, previously, suddenly spoke to me very strongly. For instance, when Sam talks to Frodo about a father reading to his son (on the outskirts of Mordor), it meant little to me until I
was a father reading LotR to my son. And then it brought tears to my eyes.
Likewise, it should be obvious that I can get more out of
Crime and Punishment than my 4-year-old daughter can, and equally clear that my 4-year-old daughter will enjoy the literary stylings of "Daisy Meadows" more than I will.
Communication is not only the speaker, but the speaker filtered through the experience, understanding, and ideas of the listener. Likewise the writer and the reader.
The depth of
Crime and Punishment exists due to the efforts of the writer, but it lies fallow until read by a reader who can actively extract that depth. If it were true that "You read, you absorb, but you don't contribute to the story. It's there, complete and intact, for you as for anyone else." then any reader would walk away from it with the same experience. I can tell you as a fact that this is not true. My experience reading the novel will differ from yours, and it will differ from my experience reading the same novel later in my life. And all these things will differ than my 11-year-old daugher, my 4-year-old daughter, or my 20-year-old son assaying the same material.
The depth of a game system exists due to the efforts of the writer, but it lies fallow until used by a player who can actively extract that depth. The game player may also partake of authorial duties, it is true, but it is still a valid analogy because the difference is in degree rather than kind.
If you "agree that some games can facilitate some types of play more easily than others", then perforce you must also accept that some of that depth is not due to the players, but due to the system. Otherwise, all games would facilitate the same degree of depth, with the same degree of ease.
System is not the only thing that matters. System may not even matter most. But to claim that system doesn't matter, that "The depth is in what we bring to the game, it's not located in the rule books", then we are guilty of failing to recognize that the depth is in the synthesis of what we bring to the game and what is in the rulebooks. The rulebooks are important.
RC