Kirito acknowledged he can’t help all of Klein’s friends.
He wasn’t able to save the Moonlit Black Cats.
He felt guilt over their death, especially Sachi’s.
He was afraid of losing Asuna before the 75th boss and before the 2nd duel with Heathcliff.
He was in a state of despair after finding out Asuna was going to marry Sugou.
He felt remorse over killing the Laughing Coffin members.
He was afraid of Death Gun.
He can’t aim with guns.
Still think Kirito’s a Gary Stu?