Song might get stale, if they just keep using it over and over again.
There's two girls and a boy. Target audience change from young adults to children?
We are now seeing the same kind of marketing that Nintendo ran for the Wii U. The difference is that people here praise it instead of complaining about it.
It's not like Nintendo changed their target audience though. Switch was always meant to sell to both genders of all ages.
What I personally don't like about Nintendo commercials is the cheesy blend between real life and video game, like a guy or a dog wearing a Mario hat all of a sudden. Wii commercials were better because they simply showed people playing games. Ultimately though, the product itself makes a bigger difference than the marketing. Switch is great while Wii U was trash, so Wii U-like commercials aren't going to stop Switch.