Oh absolutely. The Jailer was so bad even Taliesin spoke highly of Final Fantasy XIV in his Shadowlands vids. And Denathrius was actually popular despite having no interesting motivation besides power-hungry baddy, cause he was a charismatic vampire lord.
Zovaal looked, sounded, and acted boring and we only got a reason to care about his diabolical plan in the very last patch when it turned out it will involve Azeroth's World Soul somehow.
It was a disaster. Granted the patch cadence did not help either.
Thing is, I don't find the incarnates all that interesting either. I don't fucking care what iridikron wants to do. Knaifu? Yes. Azshara? Yes. Denathrius? Also yes. Alternate Universe Illidan who became the Lich King? Yes. Expansion 2 of Stone Dragon I don't care about trying to punish the Titans I also don't care about? I'll pass.