Nintendo has always had somewhat of "Kiddie" stigma attached to them. It was especially bad in the GameCube era where as the rest of the industry was focusing more and more on guns, blood, and boobs. Nintendo gave gamers cartoon Zelda, Eco Mario, and candy colored ant games as the big titles. They made attempts to win the "Mature gamer" with Metroid Prime, and Eternal Darkness. But laughable marketing, and lack of third party support prevented gamers from taking it seriously.
With Nintendo Switch, times have changed. Not only is the console much sleeker than the GameCube ever was, not only do Nintendo's newer titles feel ballsier and less risk-averse. But the gaming landscape has changed. Rocket League, Fortnite, Overwatch, Minecraft, among others are all popular with kids, teens, and adults. You still have your gritty titles, but it no longer feels like the industry is trying to grow up, as it already has. Switch also has reliable third party support for once, unlike the GameCube. And Mature games are also selling well on it.
With all this, do you feel that Switch has for the most part, completely erased Nintendo's "kiddy" image? I mean, it was understandable in the Gamecube era, and Nintendo wasn't helping at all. But with the Switch? There's no real excuse.