Soilers, you have been warned
So, we know that Lex Luthor is the sworn enemy of superman, but at least in every other portrayal, we learn why they don’t get along: from Smallville’s never getting a fair shake despite being a good friend, to the Christopher Reeve antagonist who was a criminal mastermind that just wanted to be a criminal without having to worry about someone who can beat him.
But BvS left us hanging.
This movie spent a lot of time trying to get us to push the “I believe” button on Batman’s and Superman’s rivalry, there was no time spend on Lex’s antagonism. This Lex is even a Jr. wtf? Clearly they got along as well as Sr. and Lionel, but Sr. must have been out of Jr’s life for a while before the Metropolis rampage. There is no evidence that Lexcorp was singled out during the bout.
As a businessman, he might have seen a cash cow in the man of steel, whenever there was a fight he could bid competitively to get rebuilding contracts, or he knows about his weakness, he could have developed weapons to keep him in check. In neither case would he want the milk to dry up. He would try to maintain just enough friction that people don’t feel quite safe, but he would not kill Superman so early with no others of his species on the horizon to continue the cash flow.
As a total criminal, he would want him out of the way, but he is not that kind of criminal in this movie. While he does portray being unhinged, like he is some kind of Joker like character, the DC universe already has one, The Joker, and being that off kilter would have raised flags. And if he could find out about Supe’s weakness and family ties, why could Bruce not, he is supposed to be the one that follows the rest of the possible heroes, hoping to stop them before they go over the line, that is what Batman does. (yet somehow, despite lack of evident he instinctively knows about kryptonite?)(not to mention he fails to ID the other Metas, again Bruce’s personality would have not allowed him to let such potential threats go, they may not be in Gotham, but they could come…)
Not to mention what he did to Mercy Graves. Not cool, man, not cool. We never even got to see her fight like Black Widow, her good(ish) counterpart in Marvel.
Lex and Bruce are clearly CEOs of major corporations, and they had no personal knowledge of each other? Even if Bruce let someone else take care of the day to days (its clear he gave up on a social life years ago), he was still the CEO and as such would have to make a few appearances to keep the face of the company alive (and he wouldn’t have abandoned Wayne Manor, but that is a different discussion). As counterparts, Lex and Bruce would have more interaction.
Finally, how was it so easy for him to defeat the Kryptonian Council’s edict about abominations like Doomsday? If it was really such a big problem for Krypton, there would have been more safeguards, he should have had to work a bit harder to stick it to the Man, at least show him going into the programming or hardware saying something like “The Council isn’t here, I make the decisions now…)
Doomsday’s arrival was a little too soon too, he should have been in the sequel. Brainiac or Metallo would have been a far better first villain. To be fare, at least they left Darkseid out of the picture, for the moment, if they do it right, that will be epic.