(the following is based on a lan xichen post i read a while back but cannot find now 😔)
still hammering this out, but one trait lan xichen possesses, and both jin guangyao and nie mingjue lack, is that lan xichen prioritizes the wellbeing of his sect first and foremost, above his sense of morality. when lan xichen does things that to us might read as indecisive, inactive, or immoral, it isn't that he's being stupid or blind to evil or taking the easy way out or whatever - rather, he is making the deliberate choice to prioritize his sect's wellbeing and political stability/standing above his sense of morality.
lan xichen's relationship with jin guangyao began with meng yao helping lan xichen hide from the wen, which allowed lan xichen to preserve his sect's texts and return to gusu lan. afterwards, his relationship with jin guangyao, though also highly personal, was beneficial to gusu lan because of the funds jin guangyao provided to rebuild the cloud recesses. in fact, during the guanyin temple confrontation, lan xichen hesitated when jin guangyao pointed this out, indicating the importance lan xichen placed on this aid.
when everyone started grilling jiang cheng on wei wuxian's attack/liberation of the qiongqi pass labor camp, lan xichen initially brought up that he'd never heard of wen qing personally killing anyone, but backed down immediately upon resistance from nie mingjue. imo, this was not because lan xichen was scared or indecisive or evil or anything, but rather because lan xichen had realized that him maintaining this position would put the lan at odds with the jin, and that qinghe nie was not going to stand with him on this.
from his narration, lan xichen was incredibly reluctant to have lan wangji whipped for injuring 33 of gusu lan's elders. but, from a political pov, he had no other recourse: shielding lan wangji from punishment would set the precedent that the main family line could flout the rules without consequence, which would destabilize intra-sect faith in gusu lan's leadership.
this is a trait that lan xichen shares with neither nie mingjue nor jin guangyao.
from my perspective, nie mingjue is someone who puts his sense of morality above the wellbeing of qinghe nie. of course, nie mingjue's sense of morality is highly informed by his duty to qinghe nie and arguably cannot be extricated from it; thus, the argument can be made that [nie mingjue's moral compass] and [nie mingjue's duty to his sect] are one and the same.
however, imo, if you truly managed to place nie mingjue in a position where he could either commit a grave moral transgression or allow qinghe nie to suffer, then nie mingjue would choose the latter. after all, when nie mingjue started fighting with jin guangyao on the jinlintai steps, and rebutted to jin guangyao saying that he owes jin guangyao his life by saying that he would just kill himself after he killed jin guangyao, i fully believe that nie mingjue meant this - had he actually succeeded in killing jin guangyao that day, he would have killed himself afterwards. this would undeniably have been very bad for all of qinghe nie, as nie huaisang was not ready to lead, and because the former nie sect leader killing a member of lanling jin in jinlintai would have lead to conflict between the jin and the nie, but this concern would not have stopped nie mingjue at all.
from my perspective, jin guangyao puts 1. his own wellbeing; and 2. his sense of morality; above his duty to lanling jin. actually, jin guangyao does not feel much of a "duty" towards lanling jin at all. rather than seeing himself as someone who exists to serve lanling jin and its interests (as is the case for nie mingjue, lan xichen, and jiang cheng), he instead sees lanling jin as a combination of something that was denied to him, something he must lead in order to fulfill his dead mother's wishes, a means to an end, and a source of suffering. due to his unique circumstances, nowhere in jin guangyao's mind exists the idea that he exists to serve lanling jin (because he literally does not; he is a bastard and was not raised as a sect heir); instead, the only entity to whom jin guangyao feels duty-bound is his mother.
due to this, i would argue that jin guangyao puts his sense of morality above any duty he feels towards lanling jin specifically. beyond a means to fulfill his dead mother's wishes and a means by which he can advance himself, lanling jin has no further value or attachment for jin guangyao; thus, jin guangyao is free to put other priorities before it. this is evidenced by jin guangyao's watchtower project - the project faced heavy criticism and pushback, and the benefits this project created for lanling jin specifically are largely insubstantial (i do not subscribe to the wen supervisory offices 2.0 theory), but jin guangyao invested significant amounts of his own resources and lanling jin's resources in order to make this project a reality anyways. in my opinion, he did this out of a genuine desire to help the common people.
thus, neither nie mingjue nor jin guangyao share lan xichen's trait of putting the wellbeing of his sect above his sense of morality.
but who does share this trait?
