To get closer to the core of the issue, it's a question of whether a game made from the bottom up to kill you, to beat you, to make you 'lose', is a good idea.
That's pretty much what you're up against in DS, a game where every enemy is there as a legitimate threat and the level design has revolved entirely around tempting you into traps, navigating fatal precipices and, you know, just general dangerous stuff around every corner. The game really is trying to beat you. Which, conversely, means that if you're making progress through it, you can genuinely claim to be beating it.
Modern games just aren't made this way anymore for the most part. Devs don't actually want their game's players to die - they just want them to experience the threat of dying and then overcome it and recover and, if a player should die, they don't want the player to then suffer. Less frustration that way, less chance of negative word-of-mouth. You can equally ask whether or not this is good design.
Of course, there's no single right or wrong answer. It's subjective based on the tastes of the consumer and the intentions of the creator, as design tends to be.