Your last 2 paragraphs aren't really relevant to the conversation we are having. I only brought up Civil War to address a point of why it can be viewed as its own movie and why BvS cannot despite the similarities. I didn't care anymore about Tony Stark in Civil War than I did in Iron Man. Fast forwarding to my emotional investment for a character's sacrifice at movie #22 and how it compares to a character at movie #2 isn't really fair or even needed. No one argues BvS got a little too big for its britches when asking the audience to care.
Not really what I'm talking about. You don't need 20+ movies to care about a character. People teared up over Groot after he died in the first GotG movie. Idk if anyone teared up, but Iron Man 1 ended with a scene of Tony implying to have died before the next scene revealed he recovered (Avengers 1 did too, come to think of it), but people cared because they liked Tony from the onset. If Tony had actually died at the end of Iron Man 1, people would have been sad about it. Plus, plenty of movies that don't have Marvel's staying power that make people sad about their characters dying right from the first scenes.
So I don't agree that the development time Tony got is a valid distinction. It's a factor, maybe, but the important thing was that he was actually developed as a human being for the audience to care about. Superman never was.
And I should specify that I am not talking about you or me, but the general fandom. As a body, people cared about Iron Man. As a body, people didn't care about Superman dying, and that's just really bizarre to me. Like I said, I cannot recall a single instance where someone said they were actually affected by Superman dying. Meanwhile, "We....are....Groot..." has people breaking down.
Back to JL - The movie outlines what exactly is going to happen to Clark through character dialog in a very specific manner. It's not "Superman will lose his mind", it was "Superman is going to wake up and kill Batman". How could they possibly know that? They can't but the movie just rolls with it anyway. Which is what a lot of Justice League is...
I mean, if your asking about the logic of how characters would know this or why this would happen, I'll say I don't know, but I also don't think it really matters. Like, suppose in the movie they found the Motherbox Instruction Manual that explained "Can revive dead people, but they will be crazy for a period afterwards". If that happened, we'd have an answer to the logic problem of how they'd know Superman would go nuts, but the emotional conflict of this wouldn't change and no one would care.
Superman is just arbitrarily crazy for a bit until he remembers Lois exists, then he's good again. The actual problem of the scene is that it makes little emotional sense because it's just there as an "oh shit, superman turned bad maybe" temporarily panic before it's nullified. It means nothing for the characters. They'd need to fix that problem first and foremost and then they can start worrying about the logistic problems of consistent logic.
What we know for sure about Snyder's JL is that Diana, Barry, Bruce, and Arthur all fail to some degree as heroes on their own. We see a bit of it in the early trailers. The bank (or whatever the hell that place was) blows up that Wonder Woman saves in the actual movie. Originally she failed to prevent it. This happens to everyone in various ways with it linking back to Darkseid. The movie's tagline "You Can't Save The World Alone" makes sense with that in mind. They all have to 'come together' as it were to be the best of themselves. In the actual movie it's "You Can't Save The World Unless You're Superman" since he just arrives and beats the shit out of Steppenwolf with zero effort. It all directly contradicts the ending to Batman v Superman (and subsequently it's continuation in the Suicide Squad post credits scene) to come off more upbeat. But the whole movie is so "upbeat" it makes the victory hollow. Nobody really struggled emotionally, only physically. And even then it didn't matter because Superman won the day with no "I am strong" moment for anyone else. Everyone praises the "Save one" scene with Batman and Flash but it leads to no actual hero moment for Barry. Instead he just runs the wrong direction (off screen mind you), goes the other way and then gets outclassed by Superman in speed, strength and amount of people saved. All of it led to Victor finally fist pumping him and it happened so off to the side most people didn't even notice it. For those that did see it, it didn't matter. Justice League is the canon narrative line for the DCEU so circle back to my original point: BvS doesn't matter so my general thoughts now are that I dislike it because something I once immensely enjoyed has no reason to exist. Even if Civil War's greater universe narrative were stripped from the movie it still works as a sequel to Captain America: TWS. You can't look at BvS as Man of Steel 2.
That's True too. Despite being a direct sequel, JL feels like it's straight up from a different universe than BvS. Like the opening has the kids talk about what a beacon of hope Superman was when he was regarded with suspicion and threat up to the moment he died, at which point be became a martyr. But I feel like the "Hope is gone without superman" is one thing that's consistent in the different interpretations of JL we hear about, so.....idk.
