Off the top of my head, SpongeBob SquarePants, Danny Phantom, Fairly Oddparents, The Big Bang Theory and It's Always Sunny in Philadelphia all have jokes, if not the main plot point of the episode, that are just mocking the existence of LGBTQ people.
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that was the worst one I remember
even when I was a dipshit edgelord teenager who had no clue about trans issues that episode felt unusually cruel and mean spirited, even for south park