btw, I just watched book 1's finale for the first time
I'd heard how bad it was and went in prepared...
and I still wasn't prepared.
Good gravy marie.
As soon as you get to the sequence where Korra infiltrates the arena, everything goes haywire. Korra thinks she can dissuade all of Amon's followers just by talking about something she could've made up. Tenzin and kids were captured off-screen just to fill in for a threat they couldn't otherwise write. Korra hides under a table from a bloodbender. Everyone goes up against Amon, constantly forgetting he's a bloodbender. She suddenly learns how to airbend after all that time of it never taking, and not for the reasons she was supposed to learn airbending. Though I wouldn't've minded that if the second season was about airbending being her only tool as she relearned being a great avatar (instead of needing tutoring from Zaheer in season four!) And why the hell did Amon wear a fake makeup scar under his mask the ENTIRE time? (Okay that last one's nitpicky, but still.)
And then she basically becomes suicidal because she defines herself by her bending. So what happens?
Aang and all the avatars come out of absolutely NOWHERE and restore all her abilities all at once. Okay, I get this was the ending for a one-season concept, but... you know what? You can't get away with that even then, that's a terrible excuse. That is god-awful writing. As a mechanism, it annihilates any challenges an avatar should have if their past lives can come out of nowhere and give them a crazy ass buff. Did I miss the setup for that one? It blindsided me. I didn't even feel like I was watching the same show. It was some nether realm of dreams that just happened to be animated by homo sapiens.
And then she went and gave bending back to others. Okay, I... guess I see that? Aang took Ozai's away, but still... why have bendingbending if you're not gonna roll with any consequences when it's used on people we care about? It's cheap.
So, yeah. I can see why people were absolutely honked off.