4E is definitely the most gamist oriented edition of D&D bar none, and I believe at the sacrifice of simulationist elements. However, I believe narrativist play is still just as equally supported under 4E as in any other edition.
By gamist do you mean meta-game? Hostile to immersion? That's not really what Gamism means in GNS (I'm about 88% sure--I'm not really a Forgie; I've never posted there, but I have read the three central essays closely). I know what you mean though. Let me try to restate it.
Gamism just means challenge-based play, where beating the challenges garners the players some amount of real-world esteem. The new term is "Step on Up", meaning the real-world players step on up to test themselves in the game. So there has to be some element of player skill involved, and some means of recognizing it.
Simulationism in GNS can mean simulating real-world physics OR it can mean simulating a genre of fiction, or some sort of narrative structure. I think the whole conflict between 3.xers and 4thers generalizing from "WTF no Craft skills?!" is best understood as a conflict between verisimilitude-Sim and dramatic-Sim priorities, not as Simulationism vs. Gamism. Both games are pretty weak-sauce Gamism played with the skill rules and encounter guidelines btb (meaning the challenge-the-player-not-the-character competitive bite is at a low ebb).
As I understand it, the older term Dramatism covered the latter, drama simulating GNS-Sim play. Ron Edwards dumped Dramatism for Narrativism because he wanted to highlight the difference between originality and pastiche. Buuuuuut I don't think it would be so harmful to split Sim into verisimilitude-focused and Drama-focused. Many people certainly do see that as an important distinction. OK. I'll use Dramatism for the latter.
I think of 4e as
Dramatist, rather than Gamist, because the point of a lot of the rules structure is to simulate the "perfect D&D game", rather than to provide a foundation for competition per se.
For example in 4e combat, PCs are like 100 to 1 favorites against equal level monsters. The design of the system isn't really about challenging the players (this is not to say that it's completely without challenge, or that you can't make it more difficult; we're talking about priorities here). It's more about trying to simulate the "perfect battle" where the players are getting womped, almost to defeat, but then rally and win the day. Again and again.
And it does that admirably! If we take that as the design goal, then it's actually really, really smart at doing this. My disagreement would be at the level of the design goal, not the implementation.
I think the designers seriously overestimated how much fun it is to have the "perfect" battle/adventure/campaign again and again. They badly missed something here. Letting the "perfect" scenario occur naturally at some smaller percentage of the time isn't just strictly less fun. For at least this reason: the same scenario is more fun than it otherwise would be when it only happens occasionally. It's like a slot machine. It's more fun to have it pay out 200 bucks every 1000 pulls than to have it pay out 20 cents every pull.