The Nurgle book is an exception. The rules of that battletome quite literally moved me to build a Maggotkin army, which I'm quite happy with. I think the Nighthaunt/Stormcast books, too, made people excited to bring out those particular armies. I haven't played my DoK much because their book was closer to a Skaven/DoT book with few game-changing rewrites.
We've had a similar problem here. After talking to a number of players, I think it's the complexity of 3.0 and the lack of consistent releases that are keeping people away. I can sympathize with the fact that after a long day/week at work, sometimes you just want to roll dice and smash armies together. But because AoS now has so many interlocking systems: grand strategies, battle tactics, battalions, GHB specific rules, and the whole Gelato Vet thing...it's too much to remember and prepare for.
I try to say, "These things are modular, and you don't have to play with them if you don't want to." But gamers are compelled to play the way they're "supposed to" and are less willing to strip away content, even if they might have a better time with it.
TLDR: Although AoS 3 is the most balanced it's ever been, it's also the most complex, and we've strayed far from the easygoing beer-and-pretzels game we used to enjoy. Also, few actual major kits to get hyped about.