I think the difference is that Monopoly, Nethack and Mario are intended to be played short term. Of course you can lose terribly in Monopoly and Nethack elevate

I think the difference is that Monopoly, Nethack and Mario are intended to be played short term. Of course you can lose terribly in Monopoly and Nethack elevates dying to part of the gameplay. The stakes are a little different in a long-term, persistent world MMO. The Mario you died with is, for the most part, the same Mario you started with. This is not the case in an MMO. Punishing you, irrevocably, for dying in that situation is a dreadful, fun-destroying design choice. Even in platformers, it's probably telling that one of the most successful recent ones is Jon Blow's Braid where you not only don't die but you get to reverse time.