The problem with the show in the later seasons is definitely the over reliance on goofy characters. In previous seasons, demons and angels were considered a threat and could be imposing. Then in the later seasons, they become ineffectual comic relief. Every side character becomes a goofy caricature with an over the top accent. The people they meet are cartoons for the most part and the acting is terrible. Sam and Dean also become a bit goofy as well, especially Sam, who’s acting method seems to be simply a large variety of facial ticks and stuttering grunts. Jensen Ackles has too much charisma to be too bad, he’s always watchable but for the most part he becomes a goofy guy as well. The beginning seasons have comedic moments that are pretty good and used sparingly, but they really lean into it in the later seasons and lose all the horror that the early seasons had.