Just like Man of Steel has left a lasting impression on its viewers (its thousands of threads on NeoGAF over the years are proof of that), so too will Batman v Superman. Snyder makes films people want to discuss. Virulent detractors and passionate fans, with Snyder's films there is rarely a middle ground.
Batman v Superman underperformed WB's expectations, but I would put it alongside X2, Batman Begins, The Dark Knight, Iron Man 1, Watchmen, Guardians of the Galaxy, and Deadpool as films that have elevated and transformed the genre.
Snyder humanizing the characters (and giving them fallacies, obsessions, desires, passions, and faults) makes them more interesting and more fragile to me, which raises the stakes when they fight, struggle, or die.
Superman is universally known as a boring character because, according to the general populace, he is imperceptible to almost every threat, is always perfect in judgment, and has a superpower for every situation. Making Superman actually be an imperfect, impassionate spectator who learns to take on the role of protector of Earth as he grows immediately makes the character more interesting and leads to a story that is far less obvious than your typical CBM.
I realize that the film received very mixed reception, which puts me on the outside, but I love what BvS brought to the table and it is a shame that public reaction will push further DCEU movies into more popcorn fare.