"Superman was transient compared to Civil War. And Batman was never best friends with Superman."
Batman almost killed Superman, intentionally, crossing a line no good guy is supposed to. It may have been a short time, it was not comparative to the battles that took place in Cap. Batman came with the intent to kill Superman. Even while Marvel were fighting each other, No one was intentionally trying to kill the other, even making jokes about it during the fight scenes, with the exception of Winter Soldier and Iron Man who were never "brothers"
"Good guys should always be beating up and killing the evil bad guys, not their best friends."
Using this same logic, I really don't see the differentiator in BvS. Both are good guys, but their methods are quite difference and through a set of events and circumstances, they become enemies.
Ok way too much time overthinking a comic movie on my part, in the end I think the only SuperHero movie we agree on is Watchman, because that IMO was one of the best...but weren't they all friends who ended up fighting each other
....still a great movie