Nintendo explains why the lives system was removed from Super Mario Odyssey

Coming from a Game Informer interview with director Kenta Motokura...

“We thought about how a lives system would work in this kind of broad, exploration-focused game. In this sort of game, there would be a lot of different restart points. We decided not to use the lives system because it was not an element that was absolutely necessary. We also thought that it would affect some users’ desire to play because, while users who are good at the game would rarely see the (game over) screen that comes up when Mario runs out of lives, inexperienced users would probably end up seeing it frequently.”

I do agree that it makes sense to remove the traditional lives counter in a game like Super Mario Odyssey. Lives don't really matter all that much in recent Mario games. Well, perhaps the 2D outings, but the 3D games are paced/played a bit differently.