I understand what you’re saying here, and it’s a solid argument, but I’m not coming from the angle of, “These are inconsistent with Blizzard’s art design philosophy.” I can’t reasonably make that claim. What I can say is that they look tacky, and they do, particularly movement and casting animations.
I can also say that prior to the visual updates, the team was vocal about staying faithful to the original looks in their redesign. This didn’t happen. Faithful to some heretofore unknown Blizzard art standard, maybe, I guess? Faithful to the original models? No.
Sucks.
Goblins and worgens, imo, also looked real bad during their intro period. (I mean, they still do, but…) I guess the old forums aren’t around anymore or I could link you to the multiple 100+ page threads where I dogged on the worgen models. Pun intended. 
Similarly, I couldn’t even consider playing a pandaren despite the obvious high polygon count and objectively improved graphical presentation… because… they look… so goofy. Their stupid faces and movement and animations are too much for me.
I’m sure we won’t come to an agreement on this because it’s a matter of taste. Ultimately, though, my love for the classic version of the game includes the classic aesthetic. Trying to paste the ridiculous new models onto a classic backdrop is out of the question to me. So excuse the dramatic exaggeration. 