Oh wow, where do i start lol . I think glee has had too many offensive moments to mention, but one thing that's always really bothered me is that from season 3 onwards glee tried to tackle every vaguely relevant social issue under the sun- without dedicating the proper respect and effort needed for sensitive topics. It ends up feeling like cheap exploitation rather than a genuine effort to educate their audience.
Like, for example, Coach Beiste's domestic abuse storyline, or Dave's suicide attempt, or the school shooting episode- these produced some really powerful, shocking (perhaps too shocking, even) scenes, but in context they're really not great. Mostly likely they're never mentioned again. And these scenes are sandwiched in episodes alongside quirky gags and politically incorrect one liners, and yeah, it just...doesn't work.
As fondue for two mentioned, it's part of a larger problem glee has with tone- it verves wildly back and forth between broad comedy and Very Serious Drama, which means in some episodes (comeback) suicide is treated as a punchline, while in others (on my way) it's presented in stark, heartbreaking detail.
Anyway! A few Offensive Moments/trends that come to mind are:
-like, every asian joke made about Mike and Tina
-the way 'Never Been Kissed' completely robbed Beiste of dignity. Schue kissing her was patronising and uncomfortable, and seriously, what is so bad about Beiste that she's never been in a relationship?! The way the writers act like she's unlovable because she's not conventionally feminine just comes off as offensive.
- glee reducing their disabled characters to inspiration porn and sentimental life lessons in the early seasons (the deaf choir, sue's sister, finn's paralysed friend) and in later seasons trying to backpedal and makes their disabled characters weirdly mean and sexually agressive (betty, becky- even artie with his misogyny). disabled characters are rarely shown as people in their own right.
- when kurt competely dismisses quinn's problems in 'on my way', saying the world never stopped loving her?! her parents literally kicked her out of the house??
- when mercedes finally got a storyline and it was about tater tots :/
There were actually a couple lines/jokes implying that. Ignore the ugly gifs but
also, yikes, never noticed this :/