When I first found out about Korra being out of whack because she still had some poison in her, I was pretty disappointed.
It felt almost like cheapening her and mental trauma in general, to say that hey, there’s an easy, magical way out, that all her troubles are because there is a tangible, physical object inside of her causing all her problems and if she just gets it out she’ll be insta fixed! It’s a harsh truth that when it comes to mental illness and trauma, there is no magic bullet cure, so i was pretty down about the idea that for Korra, all she had to do was follow some spirits into a magical swamp to meet a guru witch who would snap her fingers and put humpty dumpty back together.
But then, the show surprised me! Again! I’m still not super super sold on the idea that it was the poison all along still inside fucking her up, but the concept that it is HER that needs to remove it, that she might be unconsciously shying away from recovery as a coping, defensive mechanism to stay hurt so that she can avoid more pain and hurt really spoke to me. That’s something that people irl really do have to overcome - that issue that your own mental state is kind of aligned against your own best interests because it’s trying to avoid more damage, that your psyche and unconscious mind are playing a big role in your recovery, or lack of it.
Sure, Korra now has remnants of the poison in herself she needs to fight - but she always still needs to deal with her mental trauma, because they go hand in hand, they don’t cancel each other out. It went from the tired and bad cliche of “magic cures all ails!” to the infinitely better “using a magical surrounding yet still illustrating realistic reactions and recovery to trauma” trope, and that’s why the Legend of Korra is one of the best shows on television, without a doubt.