Wow people. Zelda had new story, making it a new experience. As does Xenoblade. Mario kart 9 won't really offer much more than 8, some new tracks and maybe some new characters mixed with a lot of re used tracks from older games, and it won't even look better being on the same system.
If they said all new tracks, tons of new characters, tons of new modes, redid the online to make it a proper esport, and added a story mode then that would be fine, but they won't do all that. Just adding new tracks is DLC to me, and a lot won't buy it already having 8 which will look just as good.
They should wait until the next device so they can make a huge graphical leap forward with time to build tons of new features, 60fps, new online modes and give the Switch 2 the proper launch game it needs so that it won't repeat the success/failure cycle Nintendo has from one gen to the next. The long game is the only thing that matters.
I shouldn't even have to explain why a sequel to Zelda and XC would bring a lot more new elements than a sequel to a non-story mode kart racer.
I take it the bolded baseless assumptions are the crux of why you're going to completely ignore the cold hard sales data. This might blow your mind, but the point of a sequel is to be similar. Given you're a fan of Paper Mario I would think you understand why this is important. That doesn't mean completely recycling the game of course, it's not like Game Freak would be the developer here lol. After MK8, we can totally give them the benefit of the doubt and assume they will invest a lot into it.
We know nothing of BotW2's gameplay either, could be exactly the same, and we already know it looks the same, yet with it you assume more favorably. I smell bias! I'm obviously biased towards Mario Kart, but I'm not going off assumptions, only the sales numbers which very clearly indicate that Mario Kart should be highest priority to get a sequel.
Then why haven't they released multiple mario karts every generation? We know the answer, because they would just compete against each other. And most people who bought the first one wouldn't bother with the second one because they already have the Switch Mario Kart. Mario Kart isn't gonna happen. Deal with it. Mario Kart 9 will probably be Switch 2 launch title. It makes no business sense for them to try to cannibalize their best selling game with a sequel on the same system (which they've never done) that would no doubt be very similar, rather than spend those resources making a different game that will sell on its own and not cut into the sales of their biggest seller. The only people who want Nintendo to completely change their Mario Kart strategy and release two Mario Karts on a single system are some of the Wii U owners who already had 8 on the Wii U. Needless to say thats a very small percentage of Switch owners and Mario Kart 8D owners.
Mario Kart 9 isn't happened on Switch. It would be a stupid decision and would be totally changing Mario Kart from a one per system series. There would be no point in releasing another mario kart for the same system. Not gonna happen. Nobody wants this. What would you rather have, another very similar mario kart that we already have on the system, or a brand new game? 99% of people would prefer a new game.
You seriously believe Diddy Kong/F-Zero/Kirby Air Ride/etc. would sell more than MK9!?!? Those series have never come close to Mario Kart numbers, but somehow 99% of MK8D owners would suddenly jump on such a game over a sequel to their preferred series. Again, being similar is the whole point of a sequel, to get more of what we enjoyed, and it also means it's an easy bet for Nintendo as they already know people want it.