In an SoD, there is no suspense. There is "You are attacked roll your save welp that's it." It is surprise. It's a sudden "Oh no!" followed by "Welp that's it!" You have yet to comment on this.
What you do not seem to be getting is that many people who like save-or-die do not look at the game rule on its own, but consider the circumstances where it is used, and how it is used, in the game world, as part and parcel of the SoD process.
In other words, the rules are not the game, the game is not the rules.
What matters in a SoD is the way it comes into play. What matters is not that you roll, what matters in the game is IF you roll, how you come to the point where you deal with the potential of a SoD. For this, the players must be aware of the presence of lethal elements in the game setting. As a DM, you basically present the players with clues of what's awaiting them down the middle corridor where the SoD trap is. They might have found the scribbling of a monk talking about the horror down the corridor. They might see some people with their faces half melted against the wall of the corridor.
All these elements being designed as clues to allow the players to make meaningful choices as to the manner in which they want to proceed through their exploration of the dungeon. SoD is effective when it comes into play with the players being aware of its existence. For example, they might know that the shortest path to stop Lord Thormul to escape the dungeon is the middle corridor with it's SoD melting trap, while the corridors to the left and right lead to other types of obstacles, if any. They have a choice before them to choose different paths to the same goal, and they can manage the risks they are taking, including taking the middle path and risking instant death.
Same thing about creatures with SoD effects. In the best scenarios, players become aware of the presence of such threatening creatures ahead, and have choices to confront, avoid, parley, etc etc with such creatures to avoid the direct confrontation with SoD effects. Of course, they can still choose to fight the creatures in question, but this means they are making a choice to confront potential SoD effects.
What matters is the circumstances that surround the rule, not the rule itself.
I personally call this "good DMing."