Wouldnt say it's the hardest, also i wouldnt say it is harder than savage. Its definitely a harder one mechanically speaking, but imho the enrage timer is very forgiving.
Also the biggest difference in my opinion: How often do all 8 people need to be alive at the same time and do mechanics properly - and in this regard i think it is easier than savage.
Our first kill had around 12 deaths and we didnt even see enrage (and no, there weren't a lot of pentamelds) - also messing mechanics up doesn't kill the whole group.
So its hectic, and i hate it as melee, but i wouldnt say its harder than savage (though you could argue for erich, which is far slower, but mechanics are still less forgiving).
Read that "hate" as generic melee hate for bosses that jump and twist around a lot - other than that i think its a great fight.