one big thing i think people outside fandom (like, all fandoms, fandom in general, not any particular one) tend to misunderstand is they know it's a subculture of people who are weirdly deeply invested in fictional media, and they hear about drama caused by people in those subcultures being unhinged in not-fun ways, and they think the unhingedness comes from the fact of being overinvested in works of fiction.
which is a natural assumption, but in my experience that's not really the case? like in my experience the drama llamas in fandom are usually not the ones who are just genuinely very deeply into the fiction. i've known people who are basically thinking about star trek or x-men comics or supernatural pretty much 100% of their free time and ime that type of person is usually very nice and surprisingly functional in their regular life. when someone's a constant nexus of fandom drama it's usually not that they are obsessed with the actual work of fiction the fandom is about, it's at least one of the following:
- what they're obsessed with is not the source material but their unhealthy parasocial relationships with one or more of the people who created it
- what they're obsessed with is not the source material but some elaborate shared-universe subset of fanfic about it that's only barely related to the original at this point, and/or an esoteric reading-against-the-text reinterpretation of the source material (often if the canon is active and ongoing this leads to becoming actively hostile toward it for its inevitably increasing failure to conform to their preferred fanon)
- what they're obsessed with is not the source material but the fandom itself and gathering clout within it, so that the source material basically only exists to them as a tool for scoring points in increasingly arcane fandom disputes
and very often you get the same person doing 2 and sometimes even all 3 of these, and that's where the trouble really starts
holy shit I've never seen this articulated but OP is EXACTLY RIGHT.