I’ll go first. Mine is that I can’t stand the Deadpool movies. They are self aware and self referential to an obnoxious degree. It’s like being continually reminded that I am in a movie. I swear the success of that movie has directly lead to every blockbuster having to have a joke every 30 seconds
One of my favourites is the episode of Supernatural where they cross some barrier and end up in “our world” where they’re just actors on a tv show, magic isn’t real, and Castiel is actually a needy beta who keeps wanting to hang out.
They knew that, by that stage of the show it was just shlock so they leaned into it.
The meta episodes of supernatural were some of the best of the later seasons.