Furious 7 had the same tragic advantage as TDK along with a fan base built up over 6 films and a crap ton of fan favorite characters. Most of the major players in BvS are strangers. The names are certainly iconic - but we haven't met them. The hype will be enough to get a big opening weekend, but if the film gets an MOS style reception I can see a similar drop off in week 2.
My guess is that the film will do extremely well, but a billion dollar BO is an awful lot to expect out of this film.
We live in a time where last year, five films not only past the billion mark, they absolutely obliterated it, receiving box office that only a film as big as the original Avengers could achieve in the past, and not all of them were critically acclaimed on RT:
Minions, 55%
Jurassic World: 71%
Avengers: Age of Ultron: 74%
Furious 7: 82%
Star Wars 7: 94%
So a majority of these films weren't critically acclaimed yet still destroyed the box office.
And here's the thing about Man of Steel's second week drop off, originally it had an Opening Weekend of $116M, then the second week happened where in the heart of summer in mid June, two other films opened up, Monsters University, a sequel to a Pixar classic as loved as films like the Incredibles or Finding Nemo, opens up with an OW of 80M, thats a good part of the family audience gone, also World War Z another hyped film had a $63M OW.
So both those films had a combined OW of $143M, and all MoS had in terms of legacy was that it lived off the small financial success of its franchise predecessors Superman Returns, so not just Man of Steel but literally any other solo CBM film not named, Batman, Iron Man or Avengers would survive that without facing some serious financial damage.
Yet MoS didn't have a crazy drop off or anything, at the end of its run it still made more Domestically then every superhero film between its release till Ant-man excluding AOU and GOTG.
Not to mention that with the trailer views it has received up to the 10's of millions all the way to its inane social media traction.
I can safely say that this film has to be Transformers 4 level bad to make under a billion, and i highly believe that.