Nintendo's had a lot of "mature" games over the years; Bayonetta 1 & 2, Mortal Kombat 11, Doom 2016, Wolfenstein II, Witcher 3...
Yeah it's not an anamoly to be honest. Gamecube had some, Wii did too, even Wii U. There's definitely an argument for better selection, but it's not the novelty many act like it is. Particularly a port of a pretty old pc shooter.