Can't really agree with you. With mario as massive as it is. It looks like they going all out to push the switch. You're getting totk, 2d mario, princess peach game, mario rpg remake and pikmen. Seems like one of the strongest years ever for nintendo.

Not having two separate hardware lines, so 4 total platforms, to develop for simultaneously will help the transition in a huge way. That and I assume there will be a year or two transition period where a decent number of 1st party titles are cross-gen which will help make sure Switch has good late life support along with Switch 2 having good early life support. Also can’t rule out the inevitable 4K ports of various Switch titles to help pad out the lineup.

Yeah it seems like past Nintendo systems have trained people to expect a long drought at the tail end of the lifecycle, so when people see games still coming to Switch the assumption is that it has years left before replacement.

But Nintendo are in a very different place now. They're restructured the company around providing a consistent software stream. Mario Wonder this year doesn't rule out Switch 2 next year any more than Yoshi's Island on SNES in 1995 ruled out the N64 in 1996, The Last of Us on PS3 in 2013 ruled out PS4 the same year, or Pokemon Black and White on DS in 2010 ruled out 3DS in 2011.

We're used to Nintendo dropping major support like a year before a system is replaced, but it doesn't need to be that way now.

Hugely. Like everyone shit on Nintendo in 2011 for not having enough games, but their output that year was fine:

Mario Kart 7, Zelda: Skyward Sword, Super Mario 3D Land, Pilotwings Resort, Kirby: Return to Dreamland, Nintendogs + cats, Xenoblade (PAL), The Last Story (JPN), Mario Sports Mix, Rhythm Heaven Fever (JPN), Wii Play Motion, Zelda: OoT 3D, Star Fox 64 3D, ... aside from NOA of the time being stubborn bastards and refusing to release perfectly good finished games (Xenoblade) in the US, that's a monster year ... the problem ... that was split between the 3DS and Wii. 

If that was one system combined, no one would complain. 

DS even had a couple releases like Pokémon Black/White & Fossil Fighters in the West and Kirby Mass Attack globally.

Exactly, we also had Pokemon Sun & Moon release for 3DS in 2016 just 3 months before the Switch released. Skyrward Sword also released relatively close to the release of the Wii U and the Wii U was already announced by the time it came out, I don't think the game library will be a good indication of when Switch 2 will end, we've seen numerous times where A-tier games release towards the tail end of a lifecycle, and it will especially be the case with the Switch since it's the most successful platform of all time so Nintendo won't drop it as soon as Switch 2 releases.

I would say you guys are correct, but a major zelda and mario game  has me believing 2025

With ToTK and Mario Wonder ... Nintendo's late gen obligations to the Switch are largely complete. Those two games should carry the Switch for several years going forward. You really don't have a leg to stand on if you're going to say "they didn't support the system enough!", they've given it their all more or less at this point. 

And for Nintendo it worked out well because they were able to "save" the Switch's original 2D Mario to line up with the same holiday season as the Mario movie's release without having an adverse affect on the system, the other Mario platformers did more than just fine filling the Mario itch for several years, and now they have a late-gen title that can put the Switch on cruise control and they can relax about that. 

The next 3D Mario, Zelda, Mario Kart, Animal Crossing, Smash Bros., Splatoon, Xenoblade, mainline Luigi's Mansion really are all probably reserved for Switch 2, you can't even really do a 3D Mario for 2024 for Switch because it would create a huge problem for the Switch 2 where it can't then get a 3D Mario until like when? 2026? 2027 more realistically? With no new Zelda early in the product cycle for Switch 2, that's just putting that system at such a disadvantage that it's not worth even contemplating. You can't rob Peter just to pay Paul. 

I think they'll maybe do some games cross-gen, like maybe another Pokemon, maybe a Donkey Kong game, a Kirby game, Metroid Prime 4 I could see being cross-gen ... so there's that at least. 

But I think from 2024 onwards all major software development is either Switch 2-only or cross-gen. Smaller scale things like a F-Zero GX Remaster, Luigi's Mansion Dark Moon, Peach Platformer, Paper Mario: TTYD Remake maybe are Switch-only (though Switch 2 should be able to play them anyway), but I think after 2023, the Switch only projects that are major releases are going to start to thin out. As is too I suspect all the Switch games that have been coming out recently or are planned already may be 4K ready anyway, as in they'll run at 4K on Switch 2 with no fuss, all that'll be needed is a firmware update. 

I think everything will be cross-gen for 2 years. the Switch is software sells are still really strong for switch and install base is huge.   

The main problem with that though is it will hurt the Switch 2 possibly, why buy a Switch 2 if you're just getting the same games on the Switch?

Playstation/XBox owners are more conditioned to just buy new hardware on the basis of better graphics, but that doesn't work as easily for Nintendo it doesn't seem like. 

So I think in terms of things like the next 3D Mario and Mario Kart that are probably already well into development, they sorta have to be Switch 2 only most likely. Otherwise what's the sales pitch for a Switch successor? I can see like

Mario 3D Next, Mario Kart Next, Smash Bros. Next, Animal Crossing Next, Splatoon Next being Switch 2 only

Maybe 1 more Pokemon mainline game, Kirby, Donkey Kong Country platformer, Mario Party, Metroid Prime 4 maybe being cross-gen, as in they have different and better graphical elements on the Switch 2, not just a resolution boost. 

F-Zero GX Remaster, Paper Mario TTYD, Remaster, Peach platformer, Luigi's Mansion 2 Remaster, Zelda: Wind Waker Remaster, Twilight Princess remaster just being regular Switch 1 releases that maybe have a 4K patch introduced when Switch 2 arrive. 

So basically kinda three software categories if you want to put it that way.