As a Wii U owner myself, I didn't feel screwed over as there was still more than enough new stuff; Switch had over 100 first party releases in all and only like 12 of them were Wii U ports.

Only 4 out of the top 30 best selling Switch games were Wii U ports, hardly a large proportion.

For me easily the N64, not only did they do a pretty amazing jobs with entirely new gameplay genres and systems in 3D. Their output (partially thanks to Rare) was insane.

Still to this day Banjo Kazooie/Mario 64, Golden Eye and Ocarina of Time are all such industry defining experiences.

The ones that stand out the most to me are NES, GB, DS, Wii, and Switch. For me, roughly in that order, but they're all close enough that they can slide around in order from top to bottom because I know I'm succumbing to a genetic bias: if it came first, and set a precedent important to the following consoles, then it must be more influential. And, I admit, I haven't really thought hard enough about the situation to divorce the consoles from that bias without succumbing to the opposite "recency bias". So, I'll stick with my (flawed) gut feeling for now... although, probably update my opinions after seeing other arguments and further thought. So, I think right now my answer is the NES, but I'm not married to the position.

The NES, more or less, established the video gaming industry as we know it. There were a number of other consoles, but no coherency around the direction yet. Everyone was trying different things, or copying others in strategies that would ultimately fail. The most successful pre-NES strategy (IMO) was the Commodore, and that eventually failed, dissolving into the PC gaming industry. The NES wasn't the most technologically advanced console, in fact, most of its lifetime it was the least powerful on the market. It won because they balanced the right amount of power at an affordable price, and an interface/design philosophy so simple that everyone could understand it. The SNES was the NES interface on steroids: 2 buttons → Diamond face button and triggers.

GameBoy brought that strategy to handheld. It was perhaps even more pronounced here: a withered technology used in a unique way to establish an entirely new market niche which remains present to this day → although, now mostly merged into mobile gaming and the hybrid console philosophy.

The DS reiterated the NES strategy after straying for a generation (mostly with the Gamecube) was Nintendo's next big innovation. The dual-screens themselves were not so much the innovation, but a means to accommodate the core innovation - the touch screen. The reason dual screens were necessary was because of how small the LCD screens had to be on a handheld device: Folding it out, and not obscuring the action with the touch interface. This heavily influenced mobile screen design. The iPhone went with an elongated structure where most of the interfacing occurs at the bottom, leaving the top half free for viewing. The DS and iPhone Dragon Quest games work so well because they use the same principles of the action at the top, the interface at the bottom whilst the Square Final Fantasy games didn't work very well because, instead of using the portrait orientation of Dragon Quest, they went with landscape, so much of the time the interface was obscuring the action. The touch screen interface again surfaced on the Nintendo Switch, although far less pronounced than the motion controls or traditional button controls (SNES and Wii). The DS's influence dominates the sort of games most people play today.

The Wii is the strongest reiteration of the NES philosophy to date: Blue Ocean is a revised version Gunpei Yokoi's withered tech philosophy. It introduced a few things: Motion controls and unified interface that works for all past consoles. All of which are still around today. Wii was first major establishment modern virtual reality interface → the motion controls. But it is also the first iteration of the unified interface that is one of the central concepts of the Switch. It also advanced the idea of motion pointers in the form of IR, and that ancient implementation is still the best version of the pointer that we've yet seen. One day modern techs (such as gyro) will get there, though. The Wii also brought that hype that used to be exclusive to games like Super Mario Bros 3, Donkey Kong Country, and Ocarina of Time, and brought it to consoles. Prior to the Wii, consoles didn't explode onto the scene that way, they were usually introduced, a small segment (probably in the hundreds of thousands at most) were ready to buy, and then gradually people would see why they needed these: with the Wii, it was mainstream must-have hardware before it even launched with millions wanting it now! For over a year (and most of about the first three years) people were lining up at retail locations just for the chance of purchasing one → that behaviour became normalized for all major console releases, and it increased the behaviour significantly when it came to games. But with the Wii, I liken this era of Nintendo to Beatlemania → or "Wiimania" in this case.

Switch, really it's the unification of handheld and home consoles. Mostly, the Switch is to the Wii as the SNES was to the NES, but with the added benefit that it was also the successor to the handheld line. This hybridization made the Switch the most successful console in gaming history, selling hardware at the same magnitude as DS and PS2, but beating both in software releases and sales volume and velocity. There is still room yet for the Switch to innovate and further expand the market... I think it would be great for Nintendo to release a new "Switch 1" ecosystem entry model that includes many of the upgrades of the Switch 2; or even a "Switch TV" model for people who want to join the ecosystem, but can't afford the Switch 2, or even the Switch 1 in its current form. I think a $99 Switch TV model would be crazy awesome for developing markets and thrifty gamers alike. There is a lot of value in the Switch 1 library, more to come, and a lot of potential new customers that may be in the 5-25 million range.

Little tangent: My number 1 complaint about Nintendo is they abandon their platforms too readily from about the SNES era forward, 96/97 shouldn't have been the end of the SNES, merely the 60% mark, I think there was still a lot of demand for it, many people still played SNES games on the hardware or emulator, and the Wii (in my experience) was still more popular than the Wii U throughout the Wii U's lifetime (albeit, mainly games like Just Dance, Mario Kart, Skylanders, and Lego stuff), but Nintendo - once again - kept shutting things down when it could have continued another 2-5 years... I'd have loved to have seen more IR pointer shooting games, more Virtual Console support, continued advertisement shows/more channel support.

Runners Up: The SNES (diamond face buttons and triggers, still heavily in use today), followed by the N64 (analog stick, again, still heavily in use... and arguably the prong is the precursor to the Wiimote/Joycon controller), and I wish the 3DS set more lasting elements, but really its 3D visuals now exist exclusively in VR.

The Gamecube was more powerful than the PS2, only hampered by the smaller storage discs.
Same with the N64, more powerful than PS1, but PS1 has the CD storage advantage.
Wii was the first to be significantly behind the PS3, staying in the SD 480i/480p resolution while PS3 and 360 went for 720p/1080p.

The motion controls made the Wii a runaway success, copied by Kinect and PS Move. But was it really the motion controls, or Wii Sports, Wii Fit etc that created the big success. Instead of chasing the trend of ever longer more complex games, the Wii went back to the basics of 'fun' first. Easy to pick up, one button play.

The WiiU followed the low power trend closing the gap between handheld and console. Switch is pretty close to the WiiU in terms of capabilities with more modern components, same ARM architecture, making it easy to put WiiU games on the Switch. Where WiiU failed is going back to a complicated controller and the blue ocean didn't care for the upgrade to 720p/1080p output. 

Yes the main use case of the WiiU tablet became playing without the TV on, but it was marketed as much more than that:

Put it all together, Wii very successful with low power simple visuals and easy motion controls, WiiU tablet form mostly used to play off TV, time for a new handheld while console player base was lagging with the WiiU, and the Switch was born. It's basically two Wii motion controllers clicked to the side of the Switch with analog sticks added, that can be used sideways just like the Wii controllers for 2-player games without the need of the nunchuck or classic controller add-on.

Switch became a handheld that can display on the TV with the charger, no dual use case possibilities anymore. Switch took more after the Wii than the WiiU imo. Wii laid the groundwork to make Switch a success with it's games philosophy, easy motion controls, lower fidelity for cheaper, faster to produce games.

How is gameboy at last place? Without the gameboy there is no Nintendo handheld therefor Nintendo hardware would be dead.

For me it's between the N64 and the Wii.

The 64 set many standards in console graphics such as anti-aliasing, texture filtering, and perspective correct textures, while games like Mario 64 and Ocarina of Time effectively wrote the book on how games should work in full 3D, to the point where even most games made today 30 years later are steeped in their DNA.

The Wii not only popularized new ways to play via motion controls, but also brought new demographics into the medium that prior consoles failed to reach, giving rise to the "casual" gaming sector that now numbers hundreds of millions of people.

The Game Boy lineage died with the 3DS basically.

The Switch/Switch 2 is a completely different lineage at this point, yes they are portable, but the N64 (was cutting edge for 1996) and the Wii (not cutting edge, aimed at casual audiences in 2006) are home consoles with totally different philosophies. 

Switch 2 trades blows with mobile PC handhelds that are like $800-$900 and more than twice as thick and is able to run even PS5 games. That would be like a Nintendo DS being able to run PS2 games of the day ... or 3DS running PS3 games ... or GBA running PS1/N64 tier games ... those systems weren't even remotely close to being able to do that. 

1) Mario Kart 8. - 68.2~ million. (Nuts) WiiU title.
2) Breath of the Wild. 32.4~ million. WiiU title.
3) New Super Mario Bros U. - 18.25~ Million. WiiU title.

That's 33% of the Switch's best selling top 10 games.

That constitutes a "large proportion".

Gameboy died with the DS.
The DS lasted 2 generations.

Switch is it's own thing distinct from those other two distinct handheld lineups.

4 out of the top 30 though, that's like 13%, not a large proportion. And NSMBUD will be overtaken in sales soon by either Switch Sports or Mario Wonder, leaving just 2 out of the top 10.

It is if you keep it to just the top 10.

Otherwise if you expand it and start including games like Minecraft, Donkey Kong, Kirby in the top 50 etc' then it starts to favor WiiU ports once again.

If we are just talking volumes of just game sales... Over 100~ million copies of games are just WiiU ports in the top 10 which is the majority.