I feel like dungeon mechanics are a bit better, which could offset the issue with simple class rotations, but I don't think they really fine-tuned it to offset it fully. I really enjoy bosses like Mythic Tol Dagor endboss - a fun fight with interesting mechanics for a dungeon, but not all of the bosses have these. I, personally, would like to see more difficult gameplay rather than difficult rotations, but some rotations are just pure 'meh' (retri paladin, for example).
Edit: I personally think they shouldve just given some legion traits/legendary passives on the neck and make it progress like artifact weapons, instead of this weird system.