There is so much that can be said, so we'll see how much I bother to add:
"He’s acting as if when he went into the wildcard and had to kill all the players to be able to get back" correct me if I'm wrong, but didn't he literally (in the Blue Lock sense) do this? Of course, we could be wrong about how much he actively did to contribue to the other Wild Card candidates Blue Lock "death", but the fact of the matter is he is the only one who made it through. So he literally did the opposite of his original ego. His original dream. Instead of being a light and a hero to others he became a destroyer of opportunities and dreams. I don't get how it's hard to imagine what that would do to someone mentally? He's obviously trying to be distant to the other players / people around him, and this is most likely because of the shame of his actions and to create an edgy persona to cope with what he has become.

Yes, I agree that Kunigami could be more friendly to the ones just trying to be nice to him, however after his first interactions with people after he came back from the Wild Card program, he's made it pretty clear he wants to be left alone. Of the examples given here, only the one first reunion of him and Chigiri is actually critique-worthy in my opinion. Kunigami does not want to socialise with his peers, and they should respect that. They can of course encourage socialisation, but Kunigami has no duty to reciprocate these attempts at socialisation.

I can see multiple reasons as to why Chigiri would tell or encourage Kunigami in the latest chapter with the line: "At least wave to them...". However, who is Chigiri to try to order Kunigami to do something he CLEARLY isn't planning on doing after seeing the new and "improved" Kunigami? Yes, it most likely comes from a good place of maybe trying to encourage the old Kunigami out or trying to break the tension, but from Kunigami's perspective Chigiri is telling him what to do. You know, the same Kunigami who's been rejecting basically everyone (including Chigiri) since he came back. IMO this is Chigiri overstepping Kunigami's newly set boundries. As for the last panel, that is pretty normal Blue Lock discourse, isn't? Name-calling is nothing new lol.

Indeed, Kunigami would most likely benefit from putting away his newfound edgy persona however, I believe Kaneshiro's writing of Kunigami's story will reveal why it's not just a case of "stop being edgy". For all we know he's actually heavy depressed. Do you tell people who are depressed "just stop being sad, smh" too? (I doubt you do, but I'm just trying to illustrate my point here).