With the addition of a fan in the Switch 2's dock, we all knew that Nintendo's new console would probably kick out a bit more heat than its predecessor in order to manage the more technically demanding games.
According to some folks in Japan, however (thanks, Nintendo Soup), their consoles are actually overheating. Multiple users have taken to X to relay instances in which their games have crashed, the consoles' fans have gone into overdrive, or, in one case, their system simply became too hot to hold.
User @x1010_q stated (via machine translation) "Switch 2 overheating. Too intense, I couldn’t even hold the console. Without a fan, you can’t play for long". Meanwhile, @JPSjxSmUMy170 simply said "Switch 2 is overheating; the fan noise is annoying".
It's not entirely clear whether the Switch 2 consoles are definitely, irrefutably overheating in these cases, however. As demonstrated with @p_typhoon's tweet below, they merely mention that "The fan's going nuts" after an instance of Rune Factory: Guardians of Azuma crashing, but we can't say for sure that this is the root cause:
First freeze on Switch 2.
Talked to an old man in Rune Factory: Guardians of Azuma, and it froze.
The screen's still moving (background grass swaying in the wind), but I can't control anything.
The fan's going nuts, so maybe it's overheating.
Auto-save saved my butt...
It's also important to keep in mind the environmental conditions in which the Switch 2 is being played. Nintendo itself advises that users should "not place the console near a heat source, or in a location where heat can easily build up", while also ensuring that "the air vent on the dock is not covered or obstructed".
So this is clearly a potential issue that Nintendo is very much aware of. We can certainly attest to the console getting rather warm after a certain amount of time but – touch wood – we've not yet had any instances of the Switch 2 overheating.