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.
Closely related, I was just reminiscing when that one Dave Chappelle special came out where he talks about upsetting the "alphabet people". I got so excited because I thought he was gonna go off about ABC, NBC, CNN, Fox, etc. Instead it was shit about trans people being funny.
I thought he was going to talk shit about the FBI and the CIA :deeper-sadness:
Alphabet Agencies :geordi-no:
Alphabet People :geordi-yes: