(This is a subjective text based on my relation with so called "animes" and might be out of context to some degree; it's 3:15am, sorry)
What we should ask ourselves is : Is it a good SHOW? or a bad SHOW?
Avatar - The last airbender was an epic show. Enjoyed the hell out of it. BTW <3 TOPH! Best Character. But I digress.
Legend of Korra was a really, really good show. Animation was great, voices: fantastic. Story Ark : It was interesting because it had similarities with what is going on IRL.
Also, side-note: they had me at steampunk.
Of course, It missed out on some character-related aspects, the Ending was indeed rushed ; I was expecting a kind of "To be Continued" ending with Amon still the main villain for the 2nd Season. I guess after a three season fight against the Fire Nation, A one season story ark kinda felt poor to me.
But they were both great, great SHOWS.
They were better, in some respect, than some more "traditional" cartoon(blasphemy, he didn't use the correct word).
Perfect example : Naruto ; which drags on and on and on. I've been watching it regulary. But every now and then I had to skip ahead, because the narration was just excruciating. Episodes of recalls, flashbacks, where there is no character development, no fight, no nothing. Just stuff that I've seen seasons ago. Or the character meets his opponents "du jour" and proceed to get freezed just before the fight. "Oh you wanted a fight today? Sorry, you can't have that. Here take our recycled animations with fancy filters on it.That'll do it." If I have to skip episodes of a show, maybe that's an indication that there is something wrong.
(I have given up on this cartoon)
Bleach had also problems in how it managed it's timeline. There were complete story arks that I skipped simply because they weren't relevant of the main storyline(and of my interest). But they were easy skips and I could carry on with my viewing without missing important stuff.
I realize these two are heavily commercialized "animes". So there had to be fillers every once in a while. But still annoying.
But, except if I missed any, Legend of Korra AND Avatar didn't suffer this cheap filler syndrome, even if it is fairly commecialized. I felt like there was structure behind all of it. If it ever had flashback. It was because we didn't knew these details. (Tarrlock's relation to Amon, Aang's life with the monks)It had purpose. At the end of an episode, the fight was done. The end of an episode brought some sort of closure. Complete opposite of other Animes for reasons explained earlier.
My point is: Anime doesn't mean Quality; Defenders of "anime's style and culture" should broaden their points of view and try enjoying japan inspired western cartoons simply because they are good shows.
(This is the best i can do in english to stand my position on the subject discussed. It probably went all sort of directions but i'm sure it is a good piece of opinion nonetheless.)