And please stop saying sentences like "to promote player agency through simulated systems-driven gameplay". What on earth is that even supposed to mean ? It sounds like 100 % marketing pr and is so unspecific that you could plaster it on any goddamn game.
This really isn't that hard.
Mechanics: actions the player can take (e.g. run, jump, shoot)
Systems: rules governing interactions in the game (e.g. physics, damage, ammo count)
Simulation: recreating some aspect of a real-life phenomenon in gameplay (e.g. light- and sound-based stealth in Thief)
Player Agency: the player's ability to exert influence over the game and make choices about how to progress through it
All games have both mechanics (inputs) and systems (rules), but some are more mechanics-driven and others more systems-driven. A platformer like Super Mario or a shooter like Doom is mostly driven by its mechanics, as the player is primarily challenged by their ability to use their basic actions to overcome obstacles in their path. A cRPG like Ultima or Wizardry is more systems-driven, as the challenge derives more from understanding the rules governing character statistics and combat. When Looking Glass Studios created Ultima Underworld, they sought to bring the dungeon crawler cRPG into the real-time first person perspective, replacing grid-based movement and dicerolls with simulated systems wherever possible. The game has physics (that can be manipulated with spells), dynamic lighting from torches and spells that illuminate the surroundings and draw attention to the player, encounters with persistent enemies that can be avoided with stealth or approached from multiple angles within the environment, a wide set of items with durability and weight, NPC bartering, sleep and hunger needs, and a list of stats and skills that affect how the player can interact with the game world. These are all simulated systems that drive gameplay, and they are constructed to give the player numerous options for how they want to interact with the game world. The fidelity of its simulation was an attempt to recreate the depth of interaction in pen and paper RPGs, which is what affords the player agency in how they solve problems presented by the game master.
While Thief is not an RPG and takes place in a linear sequence of missions, it works on the same principles: the player must use the simulated light- and sound-based stealth systems to circumvent enemies while making their way through open level environments that offer multiple approaches to the player's goals. Same for System Shock and Deus Ex, or Arkane's tribute album in Arx Fatalis, Dishonored, and Prey. You absolutely could not say the same of Super Mario, Doom, Diablo, Tetris, Devil May Cry, or even Bioshock which is often undeservedly lumped together with these games. You just have to know what the words actually mean.
