Starting with an easy game and making it more difficult tends to have players feeling persecuted, as you are going out of your way to increase difficulty, especially if turning those dials involves removing options or abilities the PCs might otherwise possess. Infinite cantrips are an example.
In "session 0" we all discuss what we want and what house rules we are looking at. If we are open and honest about it, and willing to adjust if needed, it typically goes well. With this approach I have never had an issue with making the game harder.
Hardcore players: Just the computer games, some people prefer to play things on "hard mode."
So you have a location, characters, events happening in sequence, presumably some structure with an antagonist in the last room of the dungeon...
That's a story. It might be considered 'rudimentary' by some, but it's still a story.
D&D without a story is just white-room theorycrafting which is fine if you wanna not bother with the whole "Dungeon" thing and just put down a blank grid with some characters and a monster to see what the DPR and TTD are... It's what I did when playtesting the Monstrous Menagerie, in part.
But then you're not playing the game. You're just kinda testing the system.
I guess we disagree on what we consider a story. As someone else described in another thread; I think what you described is a "narrative" not a "story." There will always be a narrative, but not necessarily a story IMO.
I hate to be a broken record, but I had real high hopes for modularity in 5E. I was hoping it would act as a difficulty slider among many things. I think D&D would benefit greatly from it, but its not really needed because 5E is successful without it.
There shouldn't be one mode. It a game that's supposed to allow you to 'anything', so you should be able to play hard mode or normal mode, or easy mode, or modes that don't care about difficulty at all.
Personally? I don't like 'hard' D&D or even challenge based D&D at all. I like cooperative storytelling and good storytelling, which to me requires permadeath being only a sometimes food because pacing and continuity.
I prefer a game with a harder baseline. Starting with an easy game and making it more difficult tends to have players feeling persecuted, as you are going out of your way to increase difficulty, especially if turning those dials involves removing options or abilities the PCs might otherwise possess. Infinite cantrips are an example.
Darkest Dungeon is wonderful, but it's so hard that even the "rawr, the hardness is a big part of the appeal" designers and fanbase quietly created and then embraced a game mode that is significantly easier (although still hard), just so people could complete the game.
(Personally, I think the game's appeal is the Mike Mignola-inspired art, amazing narration and black-as-night tone as a dungeon crawler.)