For me it was encapsulated by doom 3 for the most part. Games with strong dynamic shadows like splinter cell chaos theory and stalker with a mix of shiny specular effects is timeless for me. When I go back to these games the shadows still feel as good as they did when they came out and the lighting perfectly crafting the mood. A lot of modern games now even though their fidelity on paper is much better just always feel extremely flat to me and don't pop out of the screen like they used to. It seems like they're missing contrast and UE5 seems to make this even worse where all the games using it just look like mush
maybe i'm just weird but i liked the Black Ops 2/Max Payne 3 era graphics, specially if they had the piss-filter on them.
i'm not really capable of articulating why i like them so much specifically, but something about the models having enough detail in them to immerse you in its facsimile of a real world while also not exaggerating the polygon count to an unhealthily heavy degree (looking at you, 500gbs Modern Warfare 2019), plus the weird flare-effects/mexico filters they usually had at least suggested some vague idea of a style they were aiming for, unlike the hyperrealist, bland Unreal engine slop they make nowadays