Most haven`t completed it because they didn`t throw $4000 in to a gaming system with a DDR4 based GPU to play simon says with action bars or square dance around floor graphics that one shot you. Once you know the win sauce rotations by class in this game, you can run them with a macro. All you need to do is avoid the nukes and that`s all on your GPU and internet connection being in sync.
This is why fun needs to be a first priority in a video game. Hard is an illusion.