I feel like where the line is drawn with that is entirely up to the viewer, in my opinion. Everyone’s going to have their favorite and least favorite characters and they’ll work certain scenes to their favor and that’s just how it is because Glee is generally inconsistent and discontinuous. You can pretty much make an argument for anything. It’s up to you what you forgive and overlook. It’s up to you what you find charming and lovably flawed and what you find gross and wrong. There is not one thing that everyone in the Glee fandom agrees on (I’m sure there are people who hate Mike Chang and don’t ship Barole, crazy as it seems) and arguments can be made for every side no matter what.
THAT’S JUST HOW IT IS, YO.
And I choose to love Kurt Hummel because he’s my beautiful precious naturally flawed and phenomenally acted angel.