I'm old school. I was there when someone you knew had a Pong machine. Later everyone went nuts for the Atari 2600 and then things got weird. When NES salvaged the video game market it showed that Nintendo was a powerhouse in the video game realm and I was a fan, because of certain Nintendo-specific games, and therefore I stuck with them all the way to the Gamecube and when it was revealed that there was going to be an F-Zero game on that system, I probably shouted out "hell yeah!" when I read about it.
Getting the actual game though, unfortunately was a much different experience than I had hoped for.

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As far as I know there wasn't any other F-Zero games released on any platform since the SNES and the original F-Zero was just outstanding. It was a game that blew everyone away and even though there was only a handful of tracks and a mere 4 "cars" to choose from, it was something that everyone has fond memories about back in the early 90's. EDIT: There was a game on the N64 called F-Zero X in the late 90's. I somehow managed to totally miss that... whoopsie!

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Original F-Zero had super-tight controls and was just incredibly fun in every way. All the tracks were flat and the 3D aspects of it were simulated in what would be today regarded as "poorly." It was amazing for the time period though and is regarded as one of the best games on the SNES.
F-Zero GX on the other hand, kind of disappeared into the memories of most people because while it was a visually impressive game, it was in mine and many other people's opinions, too much of a departure from the original series and it was also tough as nails.

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This game is exceptionally fast to the point where for me and many others, simply keeping track of where the hell the track is going was really tough. Blink for too long and you have flown off the track and have to be carried back to it by some emergency robot thing.

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I tried to get into this game because I felt as though there must be some sort of learning curve but it is widely regarded as being "too hard" and while I realize this is very subjective, there are a lot of people that never even completed the 2nd track in time trials.
One little mistake sends your rocket car flying wildly out of position and there are a ton of jumps where you are just taking some sort of leap of faith hoping that the track is actually going to be under you when you get to the other end.

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good luck!
Some people have called this game "ahead of its time" and while it did sell well, there wasn't as great of a reception for it as there was for the original SNES one. I experienced difficulty staying interested because if you made even a tiny mistake, you would be hard-pressed to make it to the end of a race, let alone in first to third place.
This video isn't the best but I selected it because most of us, when the GC was released, were still dealing with old-school televisions, perhaps even a CRT so the grainy nature of this video does a good job of correctly reflecting how frustrating playing such a high-speed game is. The person who made this video is clearly quite familiar with the track and still has what appears to be a lot of difficulty maintaining a position near the front. Now imagine if he crashed into one of those walls and how far that would set him back seeing as how even minor mistakes result in him getting passed by several other racers.
Blink for too long and your racer is off the track or ramming into the walls and I can see how he, someone who is clearly very good at this, really struggling with the D-pad controls to keep the racer in a straight line.
This game was a real let down for me because I kind of wanted to casual fun that the original F-Zero delivered. This game was massive, beautiful, and extremely tough... I suppose a bit too tough for my liking because I never really played it a great deal and I didn't seem much reason to even bother with couch co-op because it was already damn-near-impossible to keep track of without sharing a screen.
Of course just like with anything there are going to be differing and kind of jerk-like opinions about anything. Tons of people dedicate channels to trying to prove that F-Zero GX isn't hard, it's just a "skill issue." They love to gloat and go ahead guys! The maker of this last video does make it look easy, but that is because he is very good at it. Just like if I watch an experienced person play Elden Ring it looks like a lot of fun but if I play it myself I want to throw my controller and my PS5 out the window.
So for me I think that GX was a disappointment and the sales were not really good on it but much of this can be attributed to the fact that GameCube generally speaking wasn't a huge seller and was getting their butts kicked by Xbox and Playstation.
Did you play GX? What did you think about it? Am I wrong? Please tell me how if so!
And it happens to be the one channel from someone that has plenty of experience with normal racing games...so was doing his own analysis of most antigravity racers to a strict degree, and he felt like the game was actually not deserving of the difficulty label instead calling it skill issue. Emphasis on he and not anyone else (not counting people on the comments that may agree with the video)
There's always game specialists anywhere even for the most complex games, but I think this one case of a guy that is acquainted enough with racers (including F-Zero X, which he likes more than GX) to breeze through one of GX's most infamous challenges and using that as base for every GX player calling it skill issue/being elitist because they find it easy isn't quite right.
Not to say that there isn't elitist players, but I know there's also very skilled players that are humble and/of respectful, as well as there are players that enjoy the game even when they aren't complete masters of it.
I myself had suffered a lot a few years ago to complete Diamond Cup in Master as I had to perform well in the first four races AND kill the rival at the start of Phantom Road because I was unable to get high positions on that track lol
And for as how I like GX, I'm aware that it has a lot of quirks that can make it tough for newcomers (reliance on precise steering with the analog stick, replaying to learn tracks and use reflexes, the lack of an in-game tutorial to learn the ropes on your own), so it's not that I can't understand why you felt disappointed (you even pointed it out clearly: You played the original F-Zero for casual fun racing, but GX is made for high speed specialists).
I just felt that trying to encompass all GX enjoyers into that image of "it's just skill issue bro" wasn't right - as I mentioned before, GX for many is known to be quite tough instead of the complete opposite, so its mainly those who have mastered it (whether the basic handling or every button in the controller) to a high degree that could somehow call off the hardest challenges of it as easy.
I guess the Elden Ring comparison may be apt in that regard lol
Rant done, now curious on if you've played F-Zero X and how you feel about it. Or maybe even the GBA games which seem closer to SNES (more so Maximum Velocity even if it plays a bit weirder, but GP Legend and Climax do add X/GX elements to the Mode 7 gameplay and could be more casual friendly)
I saw a lot of videos about how once it is broken down that the game is actually too EASY and i just have to roll my eyes at vids like that. These are elite gamers and not the run of the mill casual gamer like me and certainly not the average Gamecube customer. When I observe the videos and their huge breakdowns I guess I can agree with them but these guys have clearly memorized the crap out of the tracks and know exactly what to do at every turn. For the normies playing it though, those turns came out of nowhere and what you needed to do at the turn was not at all or even possible to know.
I guess I can relate to both sides of this discussion if I was a better or more dedicated gamer but alas, it is tough for me to see the gaming world through the eyes other than the ones that I have in my head.