“Leslie and Ron”
One of the worst habits of sitcoms in their later years is retconning character development. It is always ill-advised to revert characters back to their original iterations, even if they’re the versions that fans fell in love with. In the first few episodes of its final season, Parks and Rec appeared to inexplicably be guilty of this as a time jump found Knope and Swanson at their most antagonistic ever. But then the heartbreaking backstory was revealed in a blowout bottle episode, and their friendship and our faith were restored.