A lot of this feels like speculation; we don't know for instance that this early NX concept was ever seriously considered or favoured by Iwata, Nintendo famously conceptualizes a ton of stuff that never comes close to being actually made.

The implication here that Iwata wanted a weaker Wii U esque Switch and that Kirishima came along and masterminded the Switch that we got sounds like fanfiction to me, as I've never seen any serious source for such a notion.

Seems honestly a bit gross to imply that under Iwata Switch would have flopped when the man spent his last dying days helping pave the way for the system.

No. Nintendo needs to make a technically sound console and good games. Gamecube technically was more powerful than PS2, but most cross platform games were made with better performance and graphics on the PS2. I can only really think of one game, rayman arena that was objectively better on the gamecube. I can think of dozens that were better on PS2. Not to mention Odyssey is the most baby no skill 3D mario game ever produced. Nintendo needs to make both a powerful console and produce good games. If the Wii had not been almost as bad as a gamecube it could have been something special as it had terrific games in comparison to other nintendo generations

It was a design apparently as of 2014 and they even had a chip supplier lined up (Ericsson) to go with specs (480p display, 1GB RAM, I think it even had backwards compatibility with the 3DS which is interesting I guess). And it even had the name Switch already. It had no dock and would wirelessly send a video signal to the TV (through I guess an HDMI type receiver). Oh and it had Streetpass too. It would have been cheap at least I guess, maybe $200 was what they were aiming for? 

Iwata was a nice person, but *if* they had released this variant of the Switch, it would have flopped ... the market is cruel and unforgiving (ask the Dreamcast) unfortunately. 

I don't know who prompted the change, my best guess as to what happened is this, the Tegra X1 launched in March 2015 and Nvidia really put a lot of R&D and time into it hoping it would become a big hit with tablet/even smartphone makers. Problem was the chip ran too hot at 20nm, and the Tegra X1 was not picking up vendors. Android tablet makers were aiming for cheapo tablets, and obviously Apple had their own chip (A9X). This was a big problem for Nvidia because they basically had the 20nm process just for this one chip, likely they were anticipating it would be a hit chip in lots of devices and when it wasn't taking off, I think they became desperate to find someone who could use the chip and clear their 20nm contract with TSMC. 

Tegra X1 launches in March 2015, doesn't get the traction Nvidia wanted, either they reach out to Nintendo or vice versa some time maybe in summer to fall 2015 would be my guess. The murmurs have always been that Nintendo got a hell of a deal on the Tegra X1, I suspect that is correct. They offered Nintendo a deal Nintendo couldn't say no to some time in 2015 after the Tegra X1 sort of flopped as a chip design. Maybe Iwata did approve this design, but sadly he would pass away in July 2015. 

Resident Evil 4 on GameCube stomps the shit out of the PS2 version, this looks like the gap between PS4 and PS5 games today:

Here's another example, Spider-Man rans at 60 fps most of the time on the GameCube with better image quality whereas the PS2 version is about 30 fps most of the time. 

GameCube was better hardware. Star Wars Rogue Squadron II/III, Star Fox Adventures, things like that I don't think would have looked as good on the PS2 as they did on the GameCube. 

Nintendo really should have highlighted that the had better hardware, they're way too modest and allow competitors to control the narrative with phony marketing and PR statements too often. A lot of people thought the Genesis was better hardware than the SNES because Nintendo let them get away with bullshit marketing like Blast Processing. I'm playing Mortal Kombat Collection these days and it's not even close Mortal Kombat I/II/III all look way better on the Super NES. 

I don't buy it either. If we look at Nintendo's history. From Super Game Boy. Pokemon Pack on N64. GBA Gamecube link cable. Before Wii came out Iwata talking about not being tied down to the TV and then the Wii U itself. Switch just seems the fully realized goal Nintendo wanted for years. Handheld and Console being the same and being able to game anywhere. Not tied down to a TV but get a home console experience. 

There is a retro forum I frequent and they use emu's to break down games to wireframes and count the polygons for DC,PS2 and Gamecube. Rogue Squadron 3 was pushing more polygons than PS2 can do. I think it was 9 million at it's peak. The most they saw from a PS2 game was 5-6 million. DC topped out at 3 million. This is with game logic. lighting. Textures and such. 

We don't know that Iwata was pushing for the earlier concept to be released over what we got though, the Switch as we know it may well have been decided prior to his death in July 2015 and the weaker 480P/1GB RAM one could have been canned long before that.

There was a point 3DS was going to use a Tegra 1. A point PS4 was going to have 4GB of RAM. PS3 was not going to have a GPU but two CELL's to power everything. Hell even during the SEGA Saturn's development Sony was going to make it for SEGA. Early plans and early concepts is just that. Things change quickly developing a console.

The Gamecube was better hardware but RE "stomping" the ps2 version is a gross exaggeration.  It was better but it was also letterboxed, while the ps2 version was actually 16×9.  I had both versions and preferred the ps2 because the letterboxed Gamecube resulted in a tiny little screen.  To this day I find the letterbox decision so odd.  

The issue with the Gamecube was the silly unique format via mini disks.  That held the console back, just like cartridges held the N64 back.  I also think the cute lunchbox design didn't resonate with fans.  Why Nintendo went mini disks is something I do not understand.

With the Wii, the lack of HD was absurd.  The entire concept of the Wii U was weird. 

If nothing else, with the S1 and S2, nintendo is not making stupid and silly decisions.  Everything about those two consoles makes sense given the hybrid approach.  The head scratching decisions seem gone.

Edit

And in terms of showcasing the GC, prime.  That was the game that just looked amazing for its time.  

Nintendo using their own media comes down to two things. Their paranoia about piracy. The other is the mini DVD was designed to shorten load times. Nintendo really wanted short load times for their games. Which to their credit they did do and hid others well like Metroid elevators. Was it the right choice? For them maybe but obviously not for 3rd parties. Where DC went with GD Rom because SEGA was broke and could not afford the DVD license. They wanted to but could not.