Now, on to the meat of this fascinating character. At first glance, Jiren seems standoffish, stoic, and perhaps unfriendly and selfish. Upon the revelation of his backstory, we learn that his master and family were killed by a villain that Jiren was powerless to stop. His master--the man who instilled within Jiren his passion for and love of martial arts and the cultivation of pure, inner strength--was taken from him by an evildoer, and in that moment Jiren realized two things. One: Caring about ANYTHING is meaningless without wielding the requisite might to protect it, and two: Living a life unfettered by close emotional ties serves to protect one from pain and minimizes distractions that seeks to deter one in their quest for personal growth.

In layman's terms: Jiren is heavily afflicted with PTSD. His trauma, while it doesn't fully control him, certainly plays a part in his overall nature and how he holds himself. He has formed a group of do-gooders with like-minded individuals, but he isn't close to any of them, nor is he close to any of those he saves beyond the usual "hero-victim" relationship. What appears to be a simple rude and standoffish character is eventually revealed to be yet another aspect of his complex and dual nature--Jiren WANTS to be free from the burden of the past, he WANTS to blindly place faith and trust in his friends and make that a part of his power as Goku does, but he can't. He simply cannot. And this is why he's so angered by the Saiyan's mere presence, as well as the reason behind his attack on the stands upon realizing he was losing their battle. Jiren wasn't lashing out at Goku's friends: he was lashing out at his own insecurities, trying to destroy his past demons in the only way he knows how--by brandishing the immense strength that was, ironically, cultivated as a result of those same demons.

>"The problem with Jiren is that for 99% of his screen time, he's not a character. He's a wall, a block, a gate. He's only there to block progress and because he was told to, nothing else. You can't make a wall engaging."
These are the musings of a "man" I happened upon during my travels. Clearly, the "argument" here is towards the detriment of one's enjoyment of Jiren, "asserting" that there is nothing to be learned from or enthused of. I found it particularly enlightening towards the study of the kind of person who looks upon the Great Work that is Jiren and feels nothing, instead making obfuscating excuses for why the majesty is lost to them. What would a Hun do if he looked upon the gilded gates of God, if not simply spit upon them and leave?
To touch upon the statement, is there denial that Jiren poses as an obstacle in the paths of our heroes? Of course not. It is irrefutable that Jiren is yet another hurdle for Goku and his allies to overcome. But that is precisely why Jiren is so endearing, he IS a wall, personified. Because of the idiotic whims of our lead character (who I�ll abstain from referring to as �hero� for reasons that I will make evident later), he is forced into a colosseum against his will. WHY would his personal motives and goals be significant to his enemies? He is there to be fought and beaten, then possibly forgotten. But the reverse is thereby true, Jiren has no need to worry about his opponent�s hopes and dreams. But therein is the fundamental principle that makes or breaks one�s opinion of The Grey...
Jiren does not care.
He does not care how many dragons you have slain in your quests.
He does not care how many loved ones you have risen from the ashes from.
He does not care how much time you have spent honing your own ability.
His power exists, whether you understand it or not. He has been placed in your path, whether you like it or not.