Hard dungeons are fun once... maybe twice.

And after that, people will skip them and do whatever dungeon is the easiest. Even hardcore players, because their goal at that point isn't 'to do a dungeon that challenges me' it's 'get my tomestones fuck I just need tomestones to get this thing.'

This game used to have hard dungeons, Pharos Sirius is a good example. No one did it. People wouldn't even unlock it once they knew it was hard. Any time, ever, in the history of this game, when a dungeon hasn't been faceroll loot-n-scoots, ever, every single time... people would skip it. They'd bail in roulettes. You still see people doing this to some ARR dungeons in 2021.

The community including the hardcore have shown through their actions they do not want hard dungeons.