It still feels off to make that point with the AU Draenei and Yrel. They had several characters in the MU that could have embodied that zealousness had Blizzard wished to go down this path. It would have also had more teeth as we would see the descent firsthand and be actually affected by it, rather than getting in Draenor, smashing us some crazy Draeneis, then leaving the spacegoats to stew on their failures. Last time we saw Yrel and co, they were mostly just defending themselves, and now suddenly it's gogo crusade time? The jarringness is as real as leaving Garrosh in late MoP and coming back to him being a pacifist.
Yes, it's been thirty years, but that's an excuse more than an explanation. Such drastic character changes should happen on screen, not be dropped in the lore and then be forgotten about the next day.
Also killing Durotan offscreen sucks since he was one of the only tolerable characters from WoD. And Eitrigg's dialog with Grommash is still pure idiocy.