Lol Since I love Supernatural, I gotta jump in though. XD But I'll make it relevant. Anyway, I definitely have seen the worst, and everyone's on the money that it's really just all over in fandoms. I've always seen it as a result of the fact romanticism in general, like our ability to seek it, validate it, criticize it, etc. Is high. It's VERY easy to just see it, so media is succesible to this. So FF7 having a love triangle to begin with was always set for it.
It's because of that, ships of all kinds exist beyond what would be considered conventional barriers of taboo or logical reasoning that you'd want to believe supersedes subjective desire. Because it's just so EASY, in the grand scheme, for people to romanticize. And argue—literally to the point where you have to break down the epistomology of things just to talk about something like subtext itself. And you either enjoy that or hate it. But it doesn't matter—romance is easy for people to see, whether if a judgement of it is "wrong or right". It happens easily beyond other reasoning.
So like, I'm not surprised people ship Sam/Dean despite being biological brothers, ship Elsa/Anna from Frozen, or Nezuko/Tanjiro (or people assuming they're together just by the cover alone). Beyond that for like, what requires the analytical or comprehension approach, then I'm not surprised people ship Cas/Dean waaaay before the ending of the show, even when Dean says "you're my brother too", or say Fang/Vanille who are VASTLY misunderstood and a lot information about them is purposely uncovered.
So when you get to FFVII, it's like, of course there's an LTD for 20+ years, because at the end of the day, it's SUPER easy to romanticize the triangle (+ Zack) relationships, and the writing itself opened the gateway to that viewpoint. I don't get annoyed at people for simply shipping something—it's the horrid things that can be attached to it that ruins the fun and freedom of it all, or maybe even just the sport of argumentation, too.