I find Mario Odyssey quite addictive. I think it's mostly due to trying to find all the collectibles, moons, etc. My only concern is would there be a reason to replay the game after everything has been found.
I typically need something to encourage better performance to keep me coming back. Like chasing high scores, etc. So far Odyssey's fun seems to come from exploration. The challenge level though is pretty low, and that's what concerns me.
So replay it and go slow the second time, explore everything and search for Easter eggs you may have missed the first time. Find new things to do and new places to go. In other words, have fun.
Like Zelda for example it's not super hard but as you explore you want to do as well as possible because you want to save your health and items for when you really need it. Mario you die.. Lose a couple coins, respawn, instantly get it back.. No repercussions. I dunno. It's all good though. Not that serious I guess.