OP, the dev team have designed the game to wean you into the harder mechanics, that's why the first dungeons are the way they are. Although, you must've not noticed anything in the early dungeons if you think it's all tank and spank. Sastasha gets you to interrupt the adds spawning, Tam-Tara Deepcroft gets you to attack adds because the boss is invulnerable while they are up, Copperbell gets you to attack adds otherwise you will be overwhelmed, Halatali does the same, don't get adds and you take a lot of damage, etc.

What are you complaining about OP? There are a lot more to the boss encounters than tank and spank. Are you playing with your eyes shut?