Being a console developer, I can say that these claims are false.

There's a dedicated technical requirements check by Nintendo (just as with Sony and Nintendo) called the "Lotcheck", which is the process of getting the game licensed, which in turn is the prerequisite for the seal.

The Lotcheck requirements list things like standardized Home Button behaviour, Wii Strap reminder screen behaviour, Scratched/Dirty Disc behaviour, etc.

It's not about game content.