In 2001, if you had claimed that you self identified as a sim player and your go to game for that style was D&D, everyone would look at you like you had two heads.
First off, few gamers today, and even fewer back in 2001, have any idea what 'sim' or any other GNS term means. They're theoretical modelling tools talked about by handful of people on the internet. And the people who came up with the GNS theory have always had trouble defining 'simulation', and aren't exactly fans of D&D either. Which isn't surprising, as D&D, by the standards of the theorists, is an 'incoherent' game. The fact it's also the most popular game in the hobby only rubs salt in the wound.
When did D&D become the poster child for sim play?
It's not. D&D is by far the most popular RPG in the world. In its 40 year history it has been played by millions of people in all kinds of ways.
So, I ask you, why D&D? If you like sim style play where the mechanics are making a statement about the game world, then why on Earth would you choose to play D&D?
Because I've always run D&D that way and never had a problem with it.
D&D as a 'gamist' system? Then why does it have five different kinds of coins, and dozens of different kinds and sizes of gems, rather than use an abstract wealth system? Why does the equipment guide include things like carts, chickens, and backpacks, along with the weight (down to the fraction of a pound) of each item? Have you read the AD&D DMG? It includes costs per day for masons, sages, architects, and other labourers. The exact dimensions, costs, and maneuverability of all kinds of sea-going vessels. The properties of dozens of real-world herbs. Elaborate tables showing the likelihood of encountering different creatures in all terrains and climates imaginable. Detailed lists of rare spell components. Lists of historical titles from medieval Europe and the Near East. And on and on.
What do you think the purpose is for all this content except to held the DM create verisimilitude that the campaign world is a living, breathing world, deeply rooted in medieval history, that exists independently of the game.
When I was 12 years old I didn't know anything about 'sim' or GNS (which was more than 20 years away). But me and my buddies instinctively interacted with the game in the terms of the game world. We did not use metagame knowledge to gain advantage. We wanted to think only in terms of what the characters could see and do in the game world. And we wanted the mechanics of the game to support the game world, not the metagame of the game system. So we think of a character in the game world and model him on his role in the world, not his role in the party. A worshipper of Odin might use a spear, even if that's an inferior weapon to a sword. A druid has responsibility to nature and the wilderness that may come into conflict with the goals of the rest of the party. If the PCs don't know about the powers of a particular monster, then neither do the players, and acting on that knowledge is a form of cheating. For a time, we even had only the GM track PC hit points, as we found it 'unrealistic' that the PCs would have a precise awareness of how injured they were, and thinking in terms of those numbers dispelled our immersion in the game world.
And D&D works perfectly well in this model I've described. Why switch to another game when we're happy with the one we've played for over 30 years?