Welcome to the Arena, where high-ranking warriors are transformed into spineless mush. Abandoning every ounce of common sense and any trace of doubt, you lunge onto a stage of harrowing landscapes and veiled abysses. Your new environment rejects you with lava pits and atmospheric hazards as legions of foes surround you, testing the gut reaction that brought you here in the first place. Your new mantra: Fight or be finished.
I guess I'm not fit for "love it because nostalgia" part because back in early 2000's, my actual shooter of choice was UnrealTournament, not kidding. Q3's rival, jam-packed with content, from varied maps, game modes, weapons(each has their own alt-fire) and it even comes with fun sample mutators to play around with.
Pardon me, as I would like to point out, that's how much of a fan of UT i am back then. But now, fast-forward to 2009, I've already had an experience with Q3 back in '03, but it was in '09 that I just have a little 'meh, why not?' kind of moment and jumped back into it just for kicks. Maybe just to remind myself why it never stuck to me when I first played it.
Surprisingly, it suddenly stuck to me. The moment I jumped back into the second arena and having my go at "Ranger", an AI opponent, everything "clicked" to me. Movement has weight, but not so much that it feels sticky. Inputs feels very responsive, which makes a railgun or RL kill feels earned, through proper aim, not just luck. Also, it's clear geometry builds with crisp textures made it feel detailed but not cluttered, unlike most shooters now.
Suddenly, I love how the each gun feels, as each fire feels like a quick punch thrown, a hit feels like a punch thrown that connects with satisfaction. Like a very big counter-statement not only to games back then, but for games today, Q3, for all it's "lack of content", endures. It never needs novelty, because it shows great confidence in the durability of solid fundamentals. Whereas most games gets away with wonky aiming or gets away with either sticky, or slippery movement feel because it has crapton of content. Q3 can simply be two players, in a small map with only a RocketLauncher as a sole weapon, and it's still be the game that it is.
And to touch the other great aspect that really had me suddenly fall in love with it after all those ten years that it exists, Quake 3 IS BUILT FOR MODDING.
IdTech3 is built to be sturdy against modders like myself, having a sort of miniature OS that recognizes and accepts customized gamecode(QVMs) and gamepacks('.PK3' files). Having an easy to understand(well, for me at least) structure of gamecode that is editable even with just a simple text program like notepad. And it payed off, from the number of games that stood on it, to the numbers of mods and ports that's still spawning from it. It's toolsets (like it's map editor and it's QVM compiler) still works well today. And it's game assets-basic sounds, models, and image files/formats-still recognizable for lots of known editors.
For me, as stupid-of-an-excuse it's game premise is, never had I seen a game THIS consistent with itself, ending up far more ludonarratively coherent than most 'serious' games today; "A race of bored aliens with near-godlike technology thought it was a good idea to collect the best 'fighters' from different time and space, drop them in their arenas, and them have it for their endless amusement". Clearly nothing more but a sort of replacement story for "developers made competitive shooter game", but for me it kind of works because it's a pretty good enough excuse not only to tie it's own game, but to also tie-in any appearance of unoffical game content. With a premise like that, no question is asked when one sees a railgun-wielding Mario figting a RocketLauncher carrying Homer Simpson in a map that looks like some random highschooler's house. Also love how much the term "frag" makes sense because of how it plays with the notion "is there killing if nobody dies?".
In short, as a more recent Q3A player and fan, probably than most players here. I attest, I love Quake 3 not because of how I remember fondly of it in my kid years, but because of how strong it's "basic" gameplay, and how durable it's "simple" game engine is TODAY. Most games we beg for sequel because there's far more room to improve. Quake 3? We beg the opposite because from aesthetics to gameplay; it's already the best that it can be.