When I look at them objectively, they have made them harder. Technically.

Many of the Endwalker dungeons are faster-paced, such as the Tower of Zot, or involve paying attention to things like heads, foot steps or rocks and wind like in Ktisis Hyperboreia. In The Dead Ends you have to navigate through the aoes while they are blowing at you from a certain direction. This often leads to people getting hit and sometimes being killed due to lack of Esuna.

In Azaldaal's Legacy you have to pay attention to the tentacles and honestly a lot of people just get hit by them. Then there is the laser mechanic that requires paying attention to where the safe spot is. Avoiding all the stampedes and cleaves in Lapis Manalis can take some getting used to with a busy rotation and The Aetherfont has fights that involve pre-positioning to be safe. The last fight involves looking at the tentacles and where it's facing a lot and if you don't, you'll get hit and potentially die.

So these fights have actually got a lot better from the old "move out of a red circle", it's just that alongside these better dungeon fights, tank self-heals have got better to the point where even a novice tank could probably solo everything, healing matters even less because of it, and although the mechanics got better they could hit even harder so that there is a real consequence for getting them wrong.

No matter how good dungeons get though, it's not going to make people like doing expert roulette because of the lack of variety. When you do one dungeon for 4-8 months, you become so good at it that you can do it in your sleep even if the mechanics are more deadly.