The line between Fanfic and Adaptation

I’ve noted that a lot of content has been cut from the Ron the Death Eater page (including everything related to the Trope Namer) because “they fit more under Adaptational x than this trope”. But a lot of fanfics I read aren’t indicated as adaptations. There are fics tagged ‘canon compliant’ and ‘canon compliant up to’, implying they’re meant to take place in the main canon (or a version thereof).

I THINK (and someone please correct if I'm wrong) that Ron the Death Eater is more about fandom sentiments and audience reactions, rather than individual fanworks. So Ron the Death Eater causes Adaptational Jerkass in fanfic, if that makes sense.