But if the basic casual content is boring isnt that a major problem? Shouldnt the dungeons be engaging enough for the role to feel satisfying to play? Or should the only satisfaction be in Savage and Ultimate? Several other MMOs dont have this problem since many dont have dedicated healers or if they do, the class design is made in such a way where this isnt a problem.

I think you have a problem here where the job design is so out of touch with the playerbase that it causes friction when played in current EW content and below. I do agree that going off a lvl 91 dungeon is not wise. However that 91 dungeon is for sure not as engaging as Zot or Holm from previous opening expansion dungeons.