I don't remember Super Mario Sunshine being a hot debate topic at the time. I remember it just not clicking with me, my roommate had it for GameCube and at the time when I was ~18 or w/e, and moving onto shooters and sports and fighters and open world action games, it just didn't seem to be the right game for me at the time. In the 12 months around Mario Sunshines release games like GTAIII, Halo, GTA Vice City, Metroid Prime, MGS2, Max Payne, Splinter Cell, Silent Hill 2, WWF Smackdown, FF X...... And just like, Super Mario Sunshine just wasn't a big, relevant release for me that year. Today, a new 3D Mario ... like a serious new Mario game is a once in a generation event that everybody pays attention to in the industry, but in 2002 there was so much going on of seriously all time great games, that Super Mario Sunshine was just not a relevant game in any of the enthusiast gaming circles I was in. Games like GTAIII and Vice City, like these major changes to the industry, were dominating the gaming conversations, and a Mario game where you float on water and clean graffiti for coins just didn't seem as much of a relevant game as, say, a crime drama set in the 1980s with a hollywood cast and a soundtrack that Quinten Tarrantino would be jealous of. Like, we had seen Mario games for 20 years, and they're great of course, but nobody had ever seen anything like the other games that came out in 2001 and 2002.
GameCube was much more under the radar on the forum wars, which were still primarily about Sega and Sony at this point, and then increasingly Sony and Microsoft. Today it's kind of the opposite, if you're a videogame enthusiast you're really into Nintendo consoles and love what Nintendo is doing with Breath of the Wild and the Switch; but back in 2001, 2002, if you were a videogame enthusiast, someone who took to internet forums to talk about videogames, the GameCube was a much less relevant console than the PS2, Dreamcast, and Xbox, and of course, PC. It just didn't seem as relevant to the discussion back then to me. Now, it might have been at other forums I didn't go to, like Nintendo specific forums, but in the forums that I went to which were broad enthusiast gaming communities like this one, the GameCube just wasn't as relevant as a console then.
I do think it's normal to see games get stellar reviews and then over time you reconsider them. Sunshine is the weakest 3D mario game since Mario 64, and it's an overall pretty weak platformer in retrospect. But when it came out there weren't a ton of games in that genre still doing the 3D world exploration stuff like Mario was. THis happens with a lot of games, GTAIV is another example, where it gets stellar reviews at launch and then people kinda reconsider it later, because at the time, it's being compared to Saints Row or Just Cause or something, and it's just much better than those games, but then over time, you end up comparing it to other games across genres and even other GTA games, and it ends up not holding up. I think similarly with Bioshock Infinite (although I didn't really like that game even when it came out, after finishing it I was very disappointed). There are a lot of games that break this mold though, Prey, Fallout New Vegas, Half-Life, Dishonored, where when they come out you think "eh, this isn't really that good compared to the other shooters this year......" but then over time you come to appreciate the depth and quality of the game and it ends up being re-evaluated later as a game that's better than it was the year it came out.
I think Super Mario Odyssey might be one that we reconsider down the line as more weak than the year it came out. WHen it came out, it seemed like a brilliant breath of fresh air in platforming, like, holy shit NIntendo did it again. But I think that sheen sort of wore off after a year where beyond that simple initial playthrough, there's almost no depth to the game, no reward, the point of the game is to collect moons, and what does collecting moons let you do? Well, it lets you collect more moons.
