Yes because the core franchises like Mario etc are more challenging (not because the game cheats like on many other games)/smarter than most games .
(Multiplayer has nothing to do with the game being a challenge or not. I never died in Call of Duty Modern Warfare but I constantly die in Super Mario games. And just because most other games give you an online community where its easy to find challenging players for competitive gameplay doesnt make the game a challenge itself. I can always find a person who is better anything even in farting or spitting or whatever.)
Mario is a hardcore title (because it was back in the 80s and its not plausible to change that when the games dont change much)
Call of Duty is a mainstream title. It has a multiplayer component that allows for challenging matches but here the challenge comes from other people not from the game itself. I can alwas try to get more points or have a better speedrun than another person in Mario games))
