one genre of fanfiction that seems to have mostly disappeared since i became an adult is shenanigans-type fics. like not exactly crack but just "the gang goes to 7-11" type, extremely low-stakes plot stories. the beach episodes of fanfiction. i just feel like i don't see those around so much anymore. whered they go. i miss them :(
I do wonder if we don't see these types of stories in fanfiction anymore because we don't see them in modern mainstream media, either. There doesn't seem to be any room for low stakes, character-establishing bits in books, movies or TV shows these days; everything that goes on in today's stories must Move The Plot Forward or it gets cut.
With that being the case, it might not be so surprising that the kids don't know that stories where the characters just interact with each other to show the reader who they are and what their relationships are like in the absence of anything greater also serve a purpose!