I really can't agree with the idea that gamism is any sort of threat to the purity of RPGing.
Hmmm. With gamism I would say it's not about the "purity" of the RPG experience, it's about the effective limits, or systemic boundaries, of what constitute an RPG at all.
As I see it, an RPG that attempted to be as full-bore gamist as possible would in the end not particularly resemble what would traditionally be considered a pen-and-paper RPG. It would very much look like some other entertainment form we already have, such as a tactical minis game, an MMORPG, a board game, or a collectible card game. The fact that such a product might be highly thematic, with distinct mechanical "roles," with "character-like" entities filling those roles, wouldn't magically convert the end product into an RPG. It would just remain a highly thematic "non-RPG" designed to aid players in "stepping on up."
On the other hand, an RPG that attempted to be as full-bore narrativist as possible---and we have several products that at least semi-attempt to do this, such as Amber Diceless and Fate---would very much resemble what we would consider to be a "traditional" RPG, though of course its mechanics and internal conceits would vary.
What I'm saying is, gamism has a place in RPGs. But an RPG only works as an RPG at all when there's something offered besides pure gamism. There HAS to be something else going on---narrativism, illusionism, sim, high concept sim. If there's not, "roleplaying" basically becomes exactly what WotC has been trying to sell players as "adventures" for the last 5 years: a "delve" format of loosely-linked combats, where the only "narrative" involved is the GM swapping out one set of dungeon tiles for another.
That's a totally valid way of playing a highly-thematic tactical miniatures game. Heck, I just bought the Lord of the Rings Living Card Game a couple of months ago and love it, and it's basically the same thing---a highly thematic gamist enterprise, where the entire premise is "step on up" to defeat the scenario presented on the cards. I don't dislike gamism, in fact I love it. I am an avid, avid board gamer and video gamer. I typically buy 2-3 new Eurogames a year, because I love trying out new game mechanics.
But I don't play RPGs to get the same kind of experience as I do playing the Lord of the Rings LCG. To make an RPG an RPG, gamism must always be subservient to another agenda, or else the game turns into a "not RPG."
Even those who like gamism don't play RPGs because they like "gamism," they play RPGs because
they like gamist RPGs. Without the other aspects that make an RPG and RPG, gamists wouldn't bother with them at all. They'd just keep playing their other gamist, "not RPG" pursuits.
In fact, an acquaintance of mine fit this bill to a "T" in graduate school. He was completely "into" comic books, and fantasy tropes, and sci-fi. Had a huge collection of Marvel and Dark Horse comics, and played Heroclix weekly. When I invited him to play in an RPG group, he flat refused, because he had no interest in transferring his gamist need fulfilled by Heroclix into the construct of an RPG. The "something else" offered him by an RPG held no interest to him---and that "something else" was directly related to the things Heroclix doesn't do, i.e., provide character-driven, evolving narrative structure to play.
(In some ways, there's probably a portion of frustrated gamists trying to get their "fix" from RPGs that like my acquaintance, would be better served by one of the many fantastic miniatures games out there. That way, they wouldn't have to deal with the "non-optimizers" messing up their "step on up" victories, nor sit and listen to the narrativists and "actor-stancers" moan and complain when they say they're tired of two-hour-long combats).
In this light, it makes perfect sense to me that 4e's audience shrank dramatically within 18-24 months of release, because gamists are the absolute easiest RPG audience to lose. Their fix is easily replicated by other activities, while those looking for less gamism in their RPGs likewise started looking elsewhere to a game that better suited their needs.
