I find it interesting that Zaheer’s detachment from worldly desires seems more like a way for him to escape suffering than an actual sacrifice.
He couldn’t give up his desire for P’li when she was alive because he actually wanted to remain attached to her. But, as soon as she died and that attachment felt painful rather than pleasurable, he gave it up without hesitation.
That kind of seems like a jerk move to me (though I suspect P’li herself wouldn’t mind).
This is actually something that’s sorta perturbed me about both ATLA and TLOK, that it kinda (probably unintentionally) misrepresents the idea of “detachment” (in the Buddhist sense) as being equivalent to apathy and/or not caring/loving people; the way detachment has been discussed both with Aang and Zaheer makes it out to seem that becoming detached means no longer holding/experiencing love for people. When the reality (from my limited understanding) is that detachment in Buddhism means that one stills feels compassion and love for people and the world but through an unbiased and not obsessive lens.
I think it’s important to remember that we’re dealing with characters who don’t always understand the concepts, because a lot of what you’re seeing could just be the result of Aang and Zaheer not really knowing what they’re talking about.
With Aang, his interpretation of Guru Pathik’s teachings was very much the interpretation of a twelve-year-old boy who was in love and didn’t know the difference between that and unbiased compassion. His frustration at the apparent inconsistency between the Air Chakra and the final chakra strongly implied that he was missing something, and his attempt to open his final chakra ended up resulting in tragedy, which probably wouldn’t have happened if he were meant to have done it right.
With Zaheer, his interpretation of Guru Laghima’s teachings was very much the interpretation of a zealot who saw those teachings as justification for whatever he wanted to do anyway. It’s plausible that detaching himself from concern for others was not what Laghima intended, but functioned as a dark workaround for someone like Zaheer who could actually pull it off.
The most questionable thing said by a character who actually knew what she was talking about was Yangchen’s speech to Aang about why the Avatar can never truly detach themselves:
Many great and wise Air Nomads have detached themselves and achieved spiritual enlightenment, but the Avatar can never do it, because your sole duty is to the world. Here is my wisdom for you: Selfless duty calls you to sacrifice your own spiritual needs, and do whatever it takes to protect the world.
That doesn’t necessarily imply that detachment equals apathy, though — she might just be talking about the Avatar’s need to reincarnate and remain part of the world.
On that last point: yes. The Buddhist notion of nirvana is that the enlightened person is freed from the cycle of samsara and no longer reincarnates once s/he physically dies. The Avatar can not become truly enlightened because s/he must always be reincarnated in order to serve the world. And as such, the Avatar is always bound to worldly suffering and will never achieve freedom from it.