I call bullshit on this devkit discourse. Switch 2 launched with like 20 ports, all of smaller games that clearly were just trying out the console audience, triple of what switch or Wii u received. And considering how there were not even review units, and the entire conundrum of the game key cards, they were right of waiting. They didn't port their biggest game not because of lack of devkits, but lack of trust in Nintendo not fucking up for third parties as usual.
Wait a second, so Switch 2 got triple the number of games as Switch and WiiU and therefore that proves developers were deliberately holding back? How does that work? And as for not porting their biggest games, let's see:
Bandai-Namco: Announced their biggest game pre-launch (Elden Ring)
Square Enix: Announced their biggest game pre-launch, releasing <8 months after console release (FF7 Remake)
Capcom: Third biggest franchise at launch (Street Fighter), Second biggest franchise announced day and date release for new title shortly after Switch 2 release (Resident Evil), Biggest franchise not announced but data mining suggests its in the works (Monster Hunter)
Konami: OK, this one's true
Koei-Tecmo: Possibly true depending on your point of view. Their biggest franchise was announced pre-launch and released within the launch window, but their biggest franchise is a Nintendo franchise (Hyrule Warriors). That said, Dynasty Warriors was also announced and is launching in January.
Sega-Atlus: Day 1 ports of games from Sega's two biggest franchises (Sonic and Yakuza). Admittedly true from the Atlus side.
And from the West:
Ubisoft: Announced a game they thought would be their biggest game pre launch and released within launch window (Star Wars Outlaws), also released their biggest franchise shortly afterwards (Assassin's Creed Shadows)
Warner Bros: Port of their biggest game at launch (Hogwarts)
CD Projekt: Port of their biggest game at launch (Cyberpunk)
EA: Technically speaking, announced their biggest games (Madden and Fifa). But yeah, nothing besides that
Take Two: Also announced biggest game (NBA). Technically also Civilization and Borderlands, even if the latter ended up being premature)
Epic: Upgrade to their biggest game at launch (Fortnite)
In other words, Konami and Microsoft/Bethesda/Activision are the odd ones out. So "lack of trust" does not seem to apply at all. It really does seem like Nintendo denied MS access to dev kits instead.