The problem with Korra is that the concept on paper of an already extremely capable protagonist who is pretty much perfect at everything compared to everyone else is one which requires a consistently decent level of writing to pull off given how such a concept automatically lowers the inherent tension in the story as the question is no longer "can the hero win?" but "when will the hero win?"
When paired up with an unlikable protagonist, bland side characters, and the story automatically rewarding characters with power boosts without justification or reason, it quickly turns into a turgid shitshow even before you get to the painful melodrama and retarded storylines.
Korra may not have been a total blueprint for the Rey style annoying mary sue protagonist lady who is super badass and awesome and snarky and expert at everything from the getgo, in that there were some token attempts to explain how she had been trained non stop since she was a toddler and actually allowed her to not win a couple of fights, but she was definitely one of the seeds of that idea becoming the standard in hack media land.
I mean, I think that Rey is an unholy fusion of Korra for undeserved power, Alice for obvious wanking by the directors, and Bella Swan in terms of personality, appearance, and social graces. She's a fucking compound Sue.
She can do anything, and official Disney articles have said that she has 'no weaknesses', JJ thinks that her upper limit of power is literally just how powerful the Force is (according to him wondering about that limit.) She has no enemies, everyone either absolutely loves her, is super conflicted but loves her, or is jealous of her abilities, or is unaware of her and/or a bumbling idiot. Only Snoke, the big lame Palpatine ripoff, even managed to hurt her physically. He paid for that with his life. Disney is so aware of this damning evidence that they have conducted smear campaigns on the fucking
term Mary Sue (which hilariously enough was coined by a
woman, Paula Smith) to try and invalidate that criticism.
Rey has not grown in any way over the course of the films and no increase in her power has felt justified or reasonable. Anakin grew stronger over the course of the Prequels, exponentially so, but he had the justification of being
trained by the Jedi for years. Luke clearly grew more powerful over the OT, but he survived his first (and possibly his second) duel with Vader since Vader wanted him alive anyway. He also had the justification of being trained
directly by Yoda, the fucking grandmaster of the Jedi order.
Rey has survived duels with multiple opponents who want her dead with no support or training whatsoever, and has grown even more and more powerful from her absurd starting point over the course of HOURS, having only a seriously out of character Luke give her no lessons whatsoever.
She is not human. She is not believable. She is not a strong character. Strong characters fight for what they have, and get up when they fail, again and again. They suffer. They sometimes die. They gain power and accolades by the fucking skin of their teeth. And they have failures, and emotions, and flaws.
Rey has none of that. She is a weak female character. She does not fight for herself or for others, things just
happen to go her way. She does not get up after failing: she just never fucking fails. She doesn't suffer or gain power by effort, everything just goes her way. She doesn't have emotions or flaws or any personality, she's a vehicle to drive the plot forwards. And when things aren't passively happening to her, she displays no agency at all.
